Word Study
extensor
CIDE DICTIONARY
extensor, n. [L., one who stretches. See Extend.].
A muscle which serves to extend or straighten any part of the body, as an arm or a finger; -- opposed to flexor . [1913 Webster]
OXFORD DICTIONARY
extensor, n. (in full extensor muscle) Anat. a muscle that extends or straightens out part of the body (cf. FLEXOR).
Etymology
mod.L (as EXTEND)
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