Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/84

Click to flip

84 Cards in this Set

  • Front
  • Back
  • 3rd side (hint)
a-
without
Prefix very much employed in medicine and all of the health sciences, indicating "not, without, -less" as, for example, in alexia (not read), aphagia (not eat), aphonia (not voice, voiceless).

The "a-" usually becomes "an-" before a vowel as, for example, in anemia (without blood), anophthalmia (no eye), anotia (no ear), anoxia (no oxygen).

The prefix "a-" comes from the Greek meaning "not."

ab-
away from
Prefix meaning "from, away from, off" as in abduction (movement of a limb away from the midline of the body), ablate (carry or cut away), abnormal (away from normal), absorb (to suck away). Ab in Latin means "from."

"Abs" in the plural is commonly used slang for the abdominal muscles.

ad-
toward
Latin prefix meaning "toward" and "in the direction of," as in adduction (movement of a limb toward the midline of the body), adhesion, and adrenal (toward the kidney).
ambi-
both sides
Ambiguous genitalia: Genitalia that are neither typically female nor typically male. Also known as intersexual genitalia.

Ambidextrous: 1. Able to use both the right and left hands with equal dexterity. Neither right- nor left-handed.

Ambient: Surrounding, present on all sides; encompassing. As, the ambient noise is deafening, or the ambient light is blinding. From the Latin "ambire" meaning "to go around."

an-
without
Prefix very much employed in medicine and all of the health sciences, indicating "not, without, or -less."

For example, the prefix "an" figures into these words: anemia (without blood), anophthalmia (no eye), anotia (no ear), anoxia (no oxygen).

The "an-" usually becomes "a-" before a consonant as, for example, in alexia (not read), aphagia (not eat), aphonia (not voice, voiceless).

The prefix "an-" comes from the Greek meaning "not."

ana-
up
The word "anatomy" comes from the Greek ana- meaning up or through + tome meaning a cutting. Anatomy was once a "cutting up" because the structure of the body was originally learned through dissecting it, cutting it up.

anabolism: the constructive part of metabolism concerned especially with macromolecular synthesis
ante-
before, in front of
Antenatal surgery: The surgical treatment of the fetus before birth. Also called prenatal surgery or, most often, fetal surgery.

Anteroposterior (AP): In anatomy, AP stands for anteroposterior: from front-to-back. For example, an AP X-ray of the chest is taken from front-to-back.

AP in this respect is the opposite of PA, which stands for posteroanterior: from back-to-front.

Antegrade amnesia: Amnesia in which the loss of memory relates to events that occur after a traumatic event. There is inability to recall new information. Old information can be recalled. Antegrade amnesia may follow brain trauma. Also called anterograde amnesia. This type of amnesia is in contrast to retrograde amnesia in which the lack of memory relates to events that occurred before a traumatic event.

anti-
against
Prefix generally meaning "against, opposite or opposing, and contrary." In medicine, anti- often connotes "counteracting or effective against" as in antibacterial, anti-infective, and antiviral. Sometimes medical terms containing anti- take on new meanings as has occurred with antibiotic and antibody. As a prefix, anti- may be shortened to ant- as in antacid. "Anti" is the Greek word for "against."
auto-
self
Autoimmune disease: An illness that occurs when the body tissues are attacked by its own immune system.

Autologous: In blood transfusion and transplantation, a situation in which the donor and recipient are the same person.

brady-
slow
Bradypnea: (Pronounced brad-ip-nea.) Abnormally slow breathing. A respiratory rate that is too slow.

Bradycardia: A slow heart rate, usually defined as less than 60 beats per minute.

The word bradycardia is logically derived from two Greek roots: bradys, slow + cardia, heart = slow heart.

Bradyphrenia: Slowed thought processes. Can be a side effect of certain psychiatric medications.

Bradykinesia: Slowed ability to start and continue movements, and impaired ability to adjust the body's position. Can be a symptom of neurological disorders, particularly Parkinson's disease, or a side effect of medications.

The word bradykinesia is logically derived from two Greek roots: bradys, slow + kinesis, movement = slow movement, slow motion, slow moving.
caud-
caudo-
tail
Caudal: An anatomic term meaning 1. Pertaining to the tail or the hind part. 2. Situated in or directed toward the tail or hind part. 3. Inferior to another structure, in the sense of being below it.

Caudal is also short for caudal epidural anesthesia.

The terms caudal and caudad are both derived from the Latin cauda, tail

Caudad: Toward the feet (or tail in embryology), as opposed to cranial.
Caudal: Pertaining to, situated in, or toward the tail or the hind part. Or below another structure.

Cauda equina: A bundle of spinal nerve roots that arise from the bottom end of the spinal cord. The cauda equina comprises the roots of all the spinal nerve roots below the level of the first lumbar (L1) vertebra, namely the sacral and coccygeal nerves. So named because it resembles the tail (Latin, cauda) of a horse (Latin, equus). See also Cauda equina syndrome.



cephal-
cephalo-
head
Cephalgia: Headache. (One of those things we all know but that defies an easy definition.) Literally, headache is an ache in the head. It is pain in the head. The Greek "algos" means "pain."

Cephalic: Relating to the head or the head end of the body. Situated on, in, or near the head. Cephalic is synonymous with cranial, relating to the cranium or head.

The word "cephalic" came from the Middle French "céphalique," from the Latin "cephalicus", from the Greek "kephalikos" meaning head.

chrom-
chromo-
color, colored
Chromesthesia: A type of synesthesia in which which a nonvisual stimulus causes the individual to perceive color. Color hearing is a form of chromesthesia. In color hearing a musical tone elicits a color. One well-studied case involved an art teacher who had a range of consistent linkages between tone and color. For her, high octaves tended to evoke a lighter color value, while lower octaves evoked a darker color value. And rapid major chord tone sequences elicited rapid flashes of colors, "somewhat like fireworks exploding."

Chromatophobia: An abnormal and persistent fear of money. Sufferers experience undue anxiety even though they realize their fear is irrational. They worry that they might mismanage money or that money might live up to its reputation as "the root of all evil." Perhaps they remember well the ill fortune that befell the mythical King Midas. His wish that everything he touched be turned to gold was fulfilled, and even his food was transformed into gold.

"Chromatophobia" is derived from the Greek "chrimata" (money) and "phobos" (fear). The "chrome" in "chromatophobia" may also be related to the Greek word "chroma" (color) because of the brilliant colors of ancient coins--for example, gold, silver, bronze and copper.

Chromosome: A visible carrier of the genetic information.
circum-
around
Prefix meaning around, surrounding, or encircling. As in circumcision, circumflex, and circumjacent. From the Latin preposition circum meaning round.

Circumflex: Curved like a bow. In anatomy, circumflex describes a structure that bends around like a bow. For example, the circumflex branch of the left coronary artery.

contra-
against
Contraindication: A condition which makes a particular treatment or procedure inadvisable. A contraindication may be absolute or relative.

An absolute contraindication is a situation which makes a particular treatment or procedure absolutely inadvisable. In a baby, for example, aspirin is absolutely contraindicated because of the danger that aspirin will cause Reye syndrome.
A relative contraindication is a condition which makes a particular treatment or procedure somewhat inadvisable but does not rule it out. For example, X-rays in pregnancy are relatively contraindicated (because of concern for the developing fetus) unless the X-rays are absolutely necessary.
A contraindication is literally contra- (against) an indication, against something that is indicated as advisable or necessary.

cry-
cryo-
cold, freezing
Cryocardioplegia: Paralysis of the heart by cold (hypothermia).

"Cryostat" is derived from the Greek "kryos" (cold) and "statos" (standing, stationary, like the cryostat chamber). "Kryos" gives us many English words, such as "cryonics" (use of coldness in medicine to bring about beneficial results) and "cryosurgery" (use of below- freezing temperatures to destroy disease). "Statos" and related Greek words give us such English words as "static" and "stationary."

cyst-
cysti-
cysto-
bladder
Cyst: A cyst is an abnormal, closed sac-like structure within a tissue that contains a liquid, gaseous, or semisolid substance. A cyst can occur anywhere in the body and can vary in size. The outer, or capsular, portion of a cyst is termed the cyst wall.

Cystectomy: Surgery to remove the bladder.

Cystoscopy: A procedure in which the doctor inserts a lighted instrument called a cystoscope into the urethra (the tube that carries urine from the bladder to the outside of the body) in order to look inside the urethra and bladder.

Cystitis: Inflammation of the bladder.
de-
away from, without
Dementia: Significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning.

Demyelination: A degenerative process that erodes away the myelin sheath that normally protects nerve fibers. Demyelination exposes these fibers and appears to cause problems in nerve impulse conduction that may affect many physical systems. Demyelinization is seen in a number of diseases, particularly multiple sclerosis.

dextr-
dextro-
right, toward the right
Prefix derived from the Latin dexter meaning "on the right side." A molecule that shows dextrorotation is turning or twisting to the right. The opposition of dextro- is levo-.
Dextrocardia: The heart is reversed and is in the right side of the chest rather than in its normal location on the left.
Dextroposition: Move to the right.

dist-
disto-
distant, distal
Distal: The more (or most) distant of two (or more) things. For example, the distal end of the femur (the thigh bone) is the end down by the knee; the end more distant from the torso. The distal bile duct is the far end of the cystic duct, the end away from the gallbladder. And the distal lymph node in a chain of nodes is the most distant one. The opposite of distal is proximal.

dys-
painful, difficult, inability, lack of function
A prefix denoting an inability or lack of function, as in dyspraxia (lack of ability to adequately control muscle movements).

Dysentery: Inflammation of the intestine, often with pain, diarrhea, bloody stools, etc. It is usually caused by infestation of the bowel by an ameba. Dysentery can be fatal, usually due to severe dehydration. Treatment includes rapid rehydration, sometimes via IV, and medication. From the Greek "dys-" meaning "abnormal or painful" + "enteron" meaning "intestine" = abnormal or painful intestine.

Dysplasia: Abnormal in form. From the Greek dys- (bad, disordered, abnormal) and plassein (to form). For example, retinal dysplasia is abnormal formation of the retina during embryonic development.

ec-
out, out of
-ectomy: A surgical suffix referring to the removal of something. For example, a lumpectomy is the surgical excision of a lump which may be benign or not, tonsillectomy is the removal of the tonsils, a partial colectomy is removal of part of the colon, an appendectomy is removal of the appendix, etc. From the Greek "ek" (out) + "tome" (a cutting) = a cutting out.

Ecchymosis: The skin discoloration caused by the escape of blood into the tissues from ruptured blood vessels. Ecchymoses can similarly occur in mucous membranes as, for example, in the mouth.


encephal-
encephalo-
brain
Encephalitis: Inflammation of the brain. Encephalitis occurs, for example, in 1 in 1,000 cases of measles.

Encephalomyelitis: Inflammation of both the brain and the spinal cord.

"Encephalo-" comes from the Greek "enkephalon", brain. "Myelitis" is inflammation of the spinal cord. Encephalomyelitis is also called myeloencephalitis.

end-
endo-
within, inner
Endochondral bone: Any bone that develops in and replaces cartilage.

The cartilage is partially or entirely destroyed by the process of calcification. The cartilage is then resorbed (reabsorbed), leaving bone in its place. Many bones are formed this way, particularly the long bones of the arms, legs, and ribs.

"Endochondral" means "within cartilage."

Endarterectomy: An operation to clean out an artery and restore normal blood flow through the artery. An endarterectomy is basically a "Rotorooter" procedure.

Endoderm: One of the three primary germ cell layers -- the other two are the mesoderm and ectoderm -- in the very early embryo. The endoderm is the innermost of the three layers. It differentiates to give rise first to the embryonic gut and then to the linings of respiratory and digestive tracts and the liver and pancreas.
epi-
upon, following
Prefix taken from the Greek that means "on, upon, at, by, near, over, on top of, toward, against, among." As in epicanthal fold (a fold of skin that comes down across the inner angle, the canthus, of the eye; epicardium (a layer of fibrous tissue that surrounds the heart and the roots of the great blood vessels); episclera (a thin membrane on top of the sclera, the white of the eye); epidural anesthetic (an anesthetic injected into the epidural space surrounding the fluid-filled sac, called the dura, around the spine which partially numbs the abdomen and legs); etc.
equi-
equal, equally
eu-
true, normal
Eugenics: Literally, meaning normal genes, eugenics aims to improve the genetic constitution of the human species by selective breeding. The use of Albert Einstein's sperm to conceive a child (by artificial insemination) would represent an attempt at positive eugenics. The Nazis notoriously engaged in negative eugenics by genocide.

Eukaryote means true nucleus.

Euthyroid: The state of having normal thyroid gland function. As opposed to hyperthyroid (overactive thyroid) and hypothyroid (underactive thyroid).

Euthanasia:The word "euthanasia" comes straight out of the Greek -- "eu", goodly or well + "thanatos", death = the good death -- and for 18th-century writers in England that was what euthanasia meant, a "good" death, a welcome way to depart quietly and well from life.

ex-
exo-
out, outside
Exocrine: Pertaining to the secretion of a substance out through a duct. The exocrine glands include the salivary glands, sweat glands and glands within the gastrointestinal tract. Exocrine is as opposed to endocrine which refers to the secretion of a substance (a hormone) into the bloodstream. The exocrine glands are the "glands of external secretion" while the endocrine glands are "glands of internal secretion."

Exogenous: Originating from outside the organism. Insulin taken by a diabetic is exogenous insulin.

Exophthalmos: Protruding eyeball. A common finding in hyperthyroidism (too much thyroid hormone) of Graves disease.
extra-
outside
Extracolonic: Outside the colon. An hereditary colon cancer syndrome may also predispose to extracolonic malignancies.

Extracranial: Outside the cranium, the bony dome that houses and protects the brain. As opposed to intracranial, inside the cranium.

heter-
hetero-
other, different
Hetero-: Combining form from the Greek "heteros" meaning "different." The opposite is "homo-" from the Greek "homos" meaning "same." For example, heterogeneous and homogeneous, heterosexual and homosexual, etc.

Heterotopic: In the wrong place, in an abnormal place, misplaced. From the Greek roots "hetero-" meaning "other" + "topos" meaning "place" = other place.

For example, heterotopic bone formation is the formation of bone where it is not normally found, as in muscle.

homo-
same
Homo-: Combining form from the Greek "homos" meaning "same." The opposite is hetero- from the Greek "heteros" meaning "different." For example, there is heterogeneous and homogeneous, heterosexual and homosexual, etc.

Homeopathy: A system of therapy based on the concept that disease can be treated with drugs (in minute doses) thought capable of producing the same symptoms in healthy people as the disease itself.

Homotrisomy: Trisomy of the same chromosome. The occurrence of two children in the same family with trisomy 21 is an instance of homotrisomy.

hydro-
water
Hydrocele: Accumulation of fluid in the coat around the testis. Small hydroceles tend to disappear by a year of age while larger hydroceles may persist and warrant surgery.

Hydrogen: The most plentiful element in the universe and one present in all organic compounds. Hydrogen is a gas with an atomic number of 1 and the symbol H.

Antoine Lavoisier coined the name hydrogen from the Greek hydro (water) + genes (forming), reflecting the fact that water is generated by the combustion of this element.

Hydronephrosis: Distention of the kidney with urine. Due to obstruction of urine outflow (for example, by a stone blocking the ureter, the tube going from the kidney to the bladder).
hyper-
above, beyond, over
Prefix meaning "high, beyond, excessive, above normal" as in hypercalcemia (high calcium in the blood) and hypersensitivity. The opposite of hyper- is hypo-.

Hyperexplexia: A genetic disorder in which babies have an exaggerated startle reflex (reaction).

hypo-
below, under
Prefix meaning "low, under, beneath, down, below normal" as in hypocalcemia (low calcium in the blood), hypoglycemia (low blood sugar) and hyposensitivity. The opposite of hypo- is hyper-.

Hypoalbuminemia: An abnormally low blood level of albumin. Normally, albumin is the most plentiful protein in human blood and the key to the regulation of its osmotic pressure.

Hypogeusia: A reduced ability to taste things (to taste sweet, sour, bitter, or salty substances).

Some people cannot detect tastes and are said to have ageusia.

im-
not
Imbibe: 1. To drink, especially alcoholic beverages. 2. To absorb or take up fluid.
From the Latin imbibere (to drink in) in the sense of consuming drink, absorbing liquids, and appropriating ideas.

Immune: Protected against infection. The Latin immunis means free, exempt.

in-
not, into
infra-
beneath, under
The term "infraspinatis" means below (infra) the spine. The infraspinatus muscle originates below the "spine" of the scapula (the wingbone).

inter-
among, between
Intercellular: Between cells, as in an intercellular bridge.

Intercurrent disease: A disease that intervenes during the course of another disease. A patient with AIDS may develop an intercurrent bout of pneumonia.

intra-
within, inside
Intracellular: Within a cell. In contrast to extracellular, meaning outside a cell.

Intracerebral hematoma: Bleeding within the brain. Diagnosis is usually by MRI or CAT scan. Treatment is by surgery.

juxta-
near
Prefix meaning near, nearby, or close.

Examples include:

Juxtaarticular -- composed of juxta, near + articular, from the Latin "articulus", a joint = near a joint. A juxtaarticular fracture is a break near a joint.
The juxtaglomerular apparatus -- a collective term referring to the cells near a structure called the glomerulus in the kidney. The juxtaglomerular cells are specialized cells that stimulate secretion of the adrenal hormone aldosterone and play a major role in renal autoregulation.
Juxtaposition -- the act of placing two or more things side by side or the state of being so placed. To lose a pair of juxtaposed teeth is to lose teeth next to one another. (Apposition is synonymous with juxtaposition).
Juxtapyloric -- means near the pylorus (the muscular area at the junction of the stomach and the first part of the small intestine, the duodenum). To speak of a juxtapyloric ulcer is to be precise about the location of the ulcer near the pylorus.
Juxtaspinal -- near the spinal column.
Juxtavescicular -- near the bladder.
Juxta- lends anatomical precision to the location of a structure. Prefixes like "juxta-" play an essential role as building blocks in the construction of many medical terms.
mal-
abnormal, bad, ill
Malaise: A vague feeling of discomfort, one that cannot be pinned down but is often sensed as "just not right."

Malaise comes straight from the French who compounded it from "mal" (bad or ill) + "aise" (ease) = ill at ease.

mes-
meso-
middle
Mesoderm: One of the three primary germ cell layers -- the other two are the ectoderm and endoderm -- in the very early embryo. The mesoderm is the middle layer. It differentiates to gives rise to a number of tissues and structures including bone, muscle, connective tissue, and the middle layer of the skin. Some cells in mesodermal tissues retain the capacity to differentiate in diverse directions. For example, some cells in the bone marrow (mesoderm) can become liver (endoderm).
meta-
change, between
Metabolic: Relating to metabolism, the whole range of biochemical processes that occur within us (or any living organism). Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances).

The term "metabolic" is often used to refer specifically to the breakdown of food and its transformation into energy.

Metatarsals: Five cylindrical bones extending from the heel (the tarsus) to the toes. The metatarsals are numbered from the inside out, so the first metatarsal extends to the big toe.

Metastasis: 1. The process by which cancer spreads from the place at which it first arose as a primary tumor to distant locations in the body.
2. The cancer resulting from the spread of the primary tumor. For example, someone with melanoma may have a metastasis in their brain. And a person with colon cancer may, fortunately, show no metastases.

Metastasis depends on the cancer cells acquiring two separate abilities -- increased motility and invasiveness. Cells that metastasize are basically of the same kind as those in the original tumor. If a cancer arises in the lung and metastasizes to the liver, the cancer cells in the liver are lung cancer cells. However, the cells have acquired increased motility and the ability to invade another organ.

The ancient Greeks used the word metastasis to mean "removal from one place to another." The plural of "metastasis" is "metastases."


mid-
middle
Midwife: A person trained to assist a woman during childbirth. Many midwives also provide prenatal care for pregnant women, birth education for women and their partners, and care for mothers and newborn babies after the birth. A midwife may be a man or a woman. Depending on local law, midwives may deliver babies in the mother's home, in a special birthing center or clinic, or in a hospital.

Midbrain aqueduct: A canal that communicates between the third and fourth ventricles in a system of four communicating cavities within the brain that are continuous with the central canal of the spinal cord.

ne-
neo-
new, newly formed
Neonate: A newborn baby.

Neonatology: The art and science of caring medically for the newborn.
pan-
all
Panacea: A universal remedy, a cure-all.

The word "panacea" comes from the name of Panaceia, the daughter of Asklepios, the Greek god of medicine (whose staff with entwined snake is the symbol of medicine). Asklepios (known to the Romans as Aesculapius) had a number of children including not only Panaceia but also Hygieia, the goddess of health (from whose name we have the word "hygiene"). Panaceia also followed her father into medicine and became the patroness of clinical medicine.

The ancients sought (but never found) a universal remedy, a panacea. (In Greek, "pan", all + "akos", remedy = remedy-all.)

par-
para-
adjacent to, near
A prefix with many meanings, including: alongside of, beside, near, resembling, beyond, apart from, and abnormal.

For example, the parathyroid glands are called "para-thyroid" because they are adjacent to the thyroid. For another example, paraumbilical means alongside the umbilicus (the belly button).

The prefix "para-" comes straight from the Greek.

per-
through
Percutaneous: Through the skin, as in a percutaneous biopsy.

Perforation of appendix: Rupture of appendix.

peri-
around
Prefix meaning around or about. For example, pericardial is around the heart, and periaortic lymph nodes are lymph nodes around the aorta.
post-
after, behind
Posterior: The back or behind, as opposed to the anterior.



Post-thrombotic syndrome: The complications that may follow deep vein thrombosis (DVT).
mal-
abnormal, bad, ill
Malaise: A vague feeling of discomfort, one that cannot be pinned down but is often sensed as "just not right."

Malaise comes straight from the French who compounded it from "mal" (bad or ill) + "aise" (ease) = ill at ease.

mes-
meso-
middle
Mesoderm: One of the three primary germ cell layers -- the other two are the ectoderm and endoderm -- in the very early embryo. The mesoderm is the middle layer. It differentiates to gives rise to a number of tissues and structures including bone, muscle, connective tissue, and the middle layer of the skin. Some cells in mesodermal tissues retain the capacity to differentiate in diverse directions. For example, some cells in the bone marrow (mesoderm) can become liver (endoderm).
meta-
change, between
Metabolic: Relating to metabolism, the whole range of biochemical processes that occur within us (or any living organism). Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances).

The term "metabolic" is often used to refer specifically to the breakdown of food and its transformation into energy.

Metatarsals: Five cylindrical bones extending from the heel (the tarsus) to the toes. The metatarsals are numbered from the inside out, so the first metatarsal extends to the big toe.

Metastasis: 1. The process by which cancer spreads from the place at which it first arose as a primary tumor to distant locations in the body.
2. The cancer resulting from the spread of the primary tumor. For example, someone with melanoma may have a metastasis in their brain. And a person with colon cancer may, fortunately, show no metastases.

Metastasis depends on the cancer cells acquiring two separate abilities -- increased motility and invasiveness. Cells that metastasize are basically of the same kind as those in the original tumor. If a cancer arises in the lung and metastasizes to the liver, the cancer cells in the liver are lung cancer cells. However, the cells have acquired increased motility and the ability to invade another organ.

The ancient Greeks used the word metastasis to mean "removal from one place to another." The plural of "metastasis" is "metastases."


mid-
middle
Midwife: A person trained to assist a woman during childbirth. Many midwives also provide prenatal care for pregnant women, birth education for women and their partners, and care for mothers and newborn babies after the birth. A midwife may be a man or a woman. Depending on local law, midwives may deliver babies in the mother's home, in a special birthing center or clinic, or in a hospital.

Midbrain aqueduct: A canal that communicates between the third and fourth ventricles in a system of four communicating cavities within the brain that are continuous with the central canal of the spinal cord.

ne-
neo-
new, newly formed
Neonate: A newborn baby.

Neonatology: The art and science of caring medically for the newborn.
pan-
all
Pandemic: An epidemic (a sudden outbreak) that becomes very widespread and affects a whole region, a continent, or the world.

By contrast:

An epidemic affects more than the expected number of cases of disease occurring in a community or region during a given period of time. A sudden severe outbreak within a region or a group as, for example, AIDS in Africa or AIDS in intravenous drug users.
An endemic is present in a community at all times but in low frequency. An endemic is continuous as in the case of malaria in some areas of the world or as with illicit drugs in some neighborhoods.
The word "pandemic" comes from the Greek "pan-", "all" + "demos", "people or population" = "pandemos" = "all the people." A pandemic affects all (nearly all) of the people. By contrast, "epi-" means "upon." An epidemic is visited upon the people. And "en-" means "in." An endemic is in the people.

par-
para-
adjacent to, near
A prefix with many meanings, including: alongside of, beside, near, resembling, beyond, apart from, and abnormal.

For example, the parathyroid glands are called "para-thyroid" because they are adjacent to the thyroid. For another example, paraumbilical means alongside the umbilicus (the belly button).

The prefix "para-" comes straight from the Greek.

per-
through
Percutaneous: Through the skin, as in a percutaneous biopsy.

peri-
around
Prefix meaning around or about. For example, pericardial is around the heart, and periaortic lymph nodes are lymph nodes around the aorta.
post-
after, behind
Postlingual: After the development of speech and language. As opposed to prelingual, before the development of speech.
pre-
before
Precancerous: Pertaining to something that is not yet overtly cancerous, but appears to be on its way to becoming a cancer. Synonymous with premalignant.

Prepubertal: Before puberty, the period during which secondary sex characteristics start to develop and the capability for sexual reproduction is attained.


pro-
supporting, in front of, before
A combining form (from both Greek and Latin) with many meanings including "before, in front of, preceding, on behalf of, in place of, and the same as." Used as a word, pro of course means professional and, in medicine, it is short for prothrombin.

Prognosis: 1. The expected course of a disease.
2. The patient's chance of recovery.
The prognosis predicts the outcome of a disease and therefore the future for the patient. His prognosis is grim, for example, while hers is good.

The word prognosis comes from the Greek prognostikos (of knowledge beforehand). It combines pro (before) and gnosis (a knowing). Hippocrates used the word prognosis, much as we do today, to mean a foretelling of the course of a disease.

pseudo-
false
Pseudodementia: A severe form of depression resulting from a progressive brain disorder in which cognitive changes mimic those of dementia.

Pseudogout: Inflammation of the joints caused by deposits of calcium pyrophosphate crystals, resulting in arthritis, most commonly of the knees, wrists, shoulders, hips, and ankles, usually affecting only one or a few joints at a time. True gout is due to a different type of crystal formed by the precipitation of uric acid.
re-
back
Reabsorption: Absorbing again. For example, the kidney selectively reabsorbs substances such as glucose, proteins, and sodium which it had already secreted into the renal tubules. These reabsorbed substances return to the blood.
retro-
behind, backward
Retrograde amnesia: Amnesia in which the lack of memory relates to events that occurred before a traumatic event. Retrograde amnesia is in contrast to antegrade amnesia in which the lack of memory relates to events that occurred after a traumatic event.

Retromingent: Urinating backwards. Also an animal such as a raccoon that urinates backwards. As in: "You have revealed yourself as a miserable, carping, retromingent vigilante, and I for one am sick of wasting my time communicating with you" (Benjamin C. Bradlee, Editor, The Washington Post). From the Latin retro- (back) + mingent from mingere (to urinate).

pan-
all
Pandemic: An epidemic (a sudden outbreak) that becomes very widespread and affects a whole region, a continent, or the world.

By contrast:

An epidemic affects more than the expected number of cases of disease occurring in a community or region during a given period of time. A sudden severe outbreak within a region or a group as, for example, AIDS in Africa or AIDS in intravenous drug users.
An endemic is present in a community at all times but in low frequency. An endemic is continuous as in the case of malaria in some areas of the world or as with illicit drugs in some neighborhoods.
The word "pandemic" comes from the Greek "pan-", "all" + "demos", "people or population" = "pandemos" = "all the people." A pandemic affects all (nearly all) of the people. By contrast, "epi-" means "upon." An epidemic is visited upon the people. And "en-" means "in." An endemic is in the people.

par-
para-
adjacent to, near
A prefix with many meanings, including: alongside of, beside, near, resembling, beyond, apart from, and abnormal.

For example, the parathyroid glands are called "para-thyroid" because they are adjacent to the thyroid. For another example, paraumbilical means alongside the umbilicus (the belly button).

The prefix "para-" comes straight from the Greek.

per-
through
Percutaneous: Through the skin, as in a percutaneous biopsy.

peri-
around
Prefix meaning around or about. For example, pericardial is around the heart, and periaortic lymph nodes are lymph nodes around the aorta.
post-
after, behind
Postlingual: After the development of speech and language. As opposed to prelingual, before the development of speech.
pre-
before
Precursor: Forerunner. That which precedes or is derived from an available source.

The term "precursor" is applied to an inactive substance converted to an active one (such as an enzyme, vitamin, or hormone). The term "precursor" applies to any chemical that is transformed into another.

From the Latin "praecursor," composed of "prae-" (or pre-), before + "curro" to run = to run before.

pro-
supporting, in front of, before
A combining form (from both Greek and Latin) with many meanings including "before, in front of, preceding, on behalf of, in place of, and the same as." Used as a word, pro of course means professional and, in medicine, it is short for prothrombin
pseudo-
false
Pseudodementia: A severe form of depression resulting from a progressive brain disorder in which cognitive changes mimic those of dementia.

re-
back
Rebound: Return of the original symptoms when maneuvers or treatment is discontinued.
retro-
behind, backward
Retroposition: 1. Simple backward displacement of a structure or organ such as the uterus.
2. In genetics, the integration of a sequence derived from RNA into a DNA genome. Messenger RNA (mRNA) is reverse-transcribed and reintegrated into the genome. Retroposition is an important mechanism of gene copying. It produces a large number of functional genes in the genome and accounts for about 10,000 duplications in the human genome.

sinist-
sinistro-
left, toward the left
sub-
below, under
Prefix meaning meaning under, below, less than normal, secondary, less than fully. As in subacute, subaortic stenosis, subarachnoid, subclavian, subclinical disease, subcutaneous, subdural, subglottis, subjacent, sublingual, subluxation, and subtotal hysterectomy. From the Latin preposition sub meaning under.
super-
above
Prefix meaning meaning above, more than normal, or excessive. As in superaspirin, superbug, superjacent, supernumerary, supersize, supertaster. From the Latin preposition super meaning above.
supra-
above, upon
sym-
together, with
Sympathetic nervous system: A part of the nervous system that serves to accelerate the heart rate, constrict blood vessels, and raise blood pressure. The sympathetic nervous system and the parasympathetic nervous system constitute the autonomic nervous system, the branch of the nervous system that performs involuntary functions.

syn-
together, with
Synesthesia: A condition in which normally separate senses are not separate. Sight may mingle with sound, taste with touch, etc. The senses are cross-wired. For example, when a digit-color synesthete sees or just thinks of a number, the number appears with a color film over it. A given number's color never changes; it appears every time with the number. Synesthesia can take many forms. A synesthete may sense the taste of chicken as a pointed object. Other synesthetes hear colors. Still others may have several senses cross-wired.

Estimates of the frequency of synesthesia range from 1 in 250,000 to 1 in 2,000. People with synesthesia are 6 times more likely to be female than male. Most synesthetes find their unusual sensory abilities enjoyable.

People with synesthesia often report that one or more of their family members also have synesthesia, so it may in at least some cases be an inherited condition.

It may be that synesthesia arises when particular senses fail to become fully independent of one another during normal development. According to this school of thought, all babies are synesthetes. Synesthesia can be induced by certain hallucinogenic drugs and can also occur in some types of seizure disorders.

The words synesthesia is a hybrid of Latin and Greek -- the Latin syn- (together) + -esthesia, from the Greek aisthesis (sensation or perception).

tachy-
rapid
Tachycardia: A rapid heart rate, usually defined as greater than 100 beats per minute. The tachycardias include sinus tachycardia, paroxysmal atrial tachycardia (PAT), and ventricular tachycardia.

trans-
through, across
Transferrin: A plasma protein that transports iron through the blood to the liver, spleen and bone marrow.

ultra-
beyond, excess
Ultrasound: High-frequency sound waves. Ultrasound waves can be bounced off of tissues using special devices. The echoes are then converted into a picture called a sonogram. Ultrasound imaging, referred to as ultrasonography, allows physicians and patients to get an inside view of soft tissues and body cavities, without using invasive techniques. Ultrasound is often used to examine a fetus during pregnancy. There is no convincing evidence for any danger from ultrasound during pregnancy.

Ultraviolet A: One of the three types of invisible light rays (together with ultraviolet B and ultraviolet C) given off by the sun.