The Collaborative International Dictionary of English v.0.48:

Crutch \Crutch\ (kr[u^]ch; 224), n.; pl. Crutches (-[e^]z).
   [OE. crucche, AS. crycc, cricc; akin to D. kruk, G.
   kr["u]cke, Dan. krykke, Sw. krycka, and to E. crook. See
   Crook, and cf. Cricket a low stool.]
   1. A staff with a crosspiece at the head, to be placed under
      the arm or shoulder, to support the lame or infirm in
      walking.
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            I'll lean upon one crutch, and fight with the other.
                                                  --Shak.
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            Rhyme is a crutch that lifts the weak alone. --H.
                                                  Smith.
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   2. A form of pommel for a woman's saddle, consisting of a
      forked rest to hold the leg of the rider.
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   3. (Naut.)
      (a) A knee, or piece of knee timber.
      (b) A forked stanchion or post; a crotch. See Crotch.
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