crutch 
(krŭch)
(krŭch)n.
1. A support used by an injured or disabled person, often in pairs, as an aid to walking, having a vertical shaft that is sometimes forked, a horizontal grip for the hand, and a crosspiece that is positioned under the armpit or a cuff that wraps around the forearm.
2. Something on which one depends, often excessively: a mnemonic crutch.
3. A forked support or part.
4. A forked leg rest on a sidesaddle.
5. Archaic The crotch of a person or animal.
v. crutched, crutch·ing, crutch·es
v.intr.
To move using a crutch or crutches.
v.tr.
To support on a crutch or crutches.
[Middle English crucche, from Old English crycc.]
crutch
crutchtop: axillary crutches
bottom: forearm crutches