elbow, arm
肘 centers on the elbow joint, the part of the arm that bends. The broader 'arm' sense is a natural extension from this key joint.
肘 combines the flesh radical ⺼ (body part) with 寸, which here likely represents a hand or measurement, together indicating the elbow area.
The flesh radical ⺼ marks a body part, and 寸 looks like a hand measuring. Picture measuring from the hand up to the elbow: that's 肘.
For チュウ, imagine chewing on your elbow (you can't, but it's a funny image): chew -> チュウ, and the elbow is the joint you're trying to reach.
elbow
armrest (of a chair); elbow rest
shoulders and elbows
tennis elbow
both elbows
restraint; restriction; control; check
one elbow
to stick out one's elbows
(detachable) elbow rest; arm rest; elbow pad
elbow strike (karate)
armchair; chair with arm rests
ancon; bracket; corbel piece
resting one's head on one's arm or elbow
elbowing (someone)
elbowing (someone)
elbow joint
olecranon
olecranon bursitis
olecranoid bursitis; miner's elbow
to put on a bold front; to act big; to be unyielding