crutch

Short definition from Wiktionary

Noun

1. 1
   A device to assist in motion as a cane, especially one that provides support under the arm to reduce weight on a leg.
2. 2
   Something or someone that supports, often used negatively to indicate that it is not needed and causes an unhealthful dependency; a prop
3. 3
   A crotch; the area of body where the legs fork from the trunk.
4. 4
   A form of pommel for a woman's saddle, consisting of a forked rest to hold the leg of the rider.
5. 5
   A knee, or piece of knee timber.
6. 6
   A forked stanchion or post; a crotch.
7. 7
   An improvised device, usually made from a piece of cardboard, to hold the last end of a joint.

Verb

1. 1
   To support on crutches; to prop up.
2. 2
   To move on crutches.
3. 3
   To shear the hindquarters of a sheep; to dag.
4. 4
   to stir with a crutch.