Forearm Bone Accompanying the Ulna
This page is the CodyCross answer for the clue below from The 1950s, Group 1811, Puzzle 3 (Smaller Waists).
Question is: Forearm Bone Accompanying the Ulna
and the answer is: RADIUS
Word Meaning:
RADIUS — (anatomy) The long bone in the forearm, on the side of the thumb.
Definitions from Wiktionary.