1. A muscle with two heads or points of origin.
a. The large muscle at the front of the upper arm that flexes the forearm.Also called biceps brachii.
b. The large muscle at the back of the thigh that flexes the knee joint.Also called biceps femoris.
[FromLatin, two-headed : bi-, two; see BI–1 + caput, head; see kaput- in the Appendix of Indo-European roots.]
(click for a larger image)biceps
left: biceps relaxed to extend forearm
right: biceps contracted to raise forearm
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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