Biceps

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

A biceps is a muscle from either of two muscle pairs (right and left) in the body. Biceps is the Latin adjective meaning two-headed. These muscles are so-called because each has two insertions at its upper end.

• In general usage, the biceps is the biceps brachii, the prominent muscle on the inside of each upper arm, popularly associated with bodily strength because it can be flexed very visibly.
• Less commonly, the biceps is the biceps femoris, one of the hamstring muscles of the underside of each thigh.

Usage note

Biceps is the singular. The muscle is often mistakenly called a bicep.