Frailty is a condition linked with age-related declination of health, which has been recognized for many decades. It is an essential challenge for aging people, and the term of frailty is broadly applied in the field of geriatrics and gerontology. Moreover, frailty is a clinical experience, it difficult to see, so the most important knowledge is defining frailty and its characteristics. Nevertheless, definition of frailty can define by the particular clinical signs and symptoms, the definite term of frailty stills elusive and ambiguous. In order to study these phenomena, theoretical development and research exploration regarding to the concept of frailty in older adults is needed. The results of this analysis may provide more information for
