Noun, pl. forearms
1. The structure and distal region of the upper limb, between the elbow and the wrist. The term forearm is used in anatomy to distinguish it from the arm, a word which is most often used to describe the entire appendage of the upper limb, but in anatomy, technically, it means only the region of the upper arm, whereas the lower “arm” is called the forearm.
2. Part of the arm, extending from the elbow to the wrist. (biology-online.org)
3. The part of the superior limb between the elbow and the wrist. (wordnetweb.princeton.edu)
Word origin: From Old English fore-, meaning “before”, superior, front + arm.