Prefixes For Numbers

Front 1

Uni-

Back 1

One

Front 2

Bi- (Diplo-)

Back 2

Two (double), twice

Front 3

Gemin-

Back 3

Double, pair

Front 4

Tri-

Back 4

Three

Front 5

Quadri-

Back 5

Four

Front 6

Tetra-

Back 6

Four

Front 7

Quint-

Back 7

Five

Front 8

Sext-, sexti-

Back 8

Six

Front 9

Sept-, septi-

Back 9

Seven

Front 10

Octa- (Octo-)

Back 10

Eight

Front 11

Nona-

Back 11

Nine

Front 12

Deca-

Back 12

Ten

Front 13

Multi-

Back 13

Many (more than one)

Front 14

Primi-

Back 14

First

Front 15

Semi-

Back 15

Half (partially)

Front 16

Hemi-

Back 16

Half, also one-sided

Front 17

Ambi-

Back 17

Both or both sides

Front 18

Null-

Back 18

None

Front 19

Pan-

Back 19

All