Muscle Nomenclature

Muscle naming falls into several broad styles based on Latin or Greek language roots: 1) a name descriptive of the shape or position of the muscle, 2) a name descriptive of what the muscle does, and 3) a mix of descriptive of the action and shape or position. Muscles are also considered to have an origin and an insertion, but these are typically not part of the naming conventions.

1) Descriptive name examples

Muscle names are often descriptive of what early anatomists judged their appearance (perhaps in a fanciful or imaginative way at times):

2) Functional name examples

The Latin terms extensor, flexor, abductor, adductor, pronator, supinator, etc. express the action of a muscle across a joint or as movement in reference to the anatomical plane. This functional nomenclature is most common for muscles acting on the hands or feet where the nomenclature generally (but not always) follows the pattern of what the muscle does, what it acts upon, and a qualifier should there be more than one muscle of that pattern.

The terms longus/brevis and minor/major tell you that there is another similar to it (you wouldn't have a long flexor qualifier if there wasn't a short flexor).  This also applies to words like “tertius” which refers to “the third” or to intermedius (in the middle).  In like manner, “superficialis” (superficial; nearer the surface) will have a companion often termed “profundus” (deeper from the surface).  There are, for example, a flexor digitorum superficialis and flexor digitorum profundus in each forearm which act upon the fingers.

3) Mixed name examples

A few muscles have an action and descriptor, or position and descriptor, as part of the name. These can be confusing as they often don't have a structure being acted upon as part of the nomenclature. 

Introduction