NOUN (2)

1. a wooden or metal staff that fits under the armpit and reaches to the ground; used by disabled person while walking;

2. anything that serves as an expedient;
- Example: "he uses drugs as a psychological crutch"

The Collaborative International Dictionary of English v.0.48:

Crutch \Crutch\, v. t.
   To support on crutches; to prop up. [R.]
   [1913 Webster]

         Two fools that crutch their feeble sense on verse.
                                                  --Dryden.
   [1913 Webster]

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.
      [1913 Webster]

            I'll lean upon one crutch, and fight with the other.
                                                  --Shak.
      [1913 Webster]

            Rhyme is a crutch that lifts the weak alone. --H.
                                                  Smith.
      [1913 Webster]

   2. A form of pommel for a woman's saddle, consisting of a
      forked rest to hold the leg of the rider.
      [1913 Webster]

   3. (Naut.)
      (a) A knee, or piece of knee timber.
      (b) A forked stanchion or post; a crotch. See Crotch.
          [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Crotch \Crotch\ (kr[o^]ch; 224), n.; pl. Crotches
   (kr[o^]ch"[e^]z). [Cf. Crotchet, Crutch.]
   1. The angle formed by the parting of two legs or branches; a
      fork; the point where a trunk divides; as, the crotch of a
      tree. more specifically, the space on the human torso
      between the two legs; also, the corresponding part between
      the legs of a pair of pants, which is in contact with the
      crotch of the wearer; as, pants with a tight crotch have
      become very popular.
      [1913 Webster +PJC]

   2. (Naut.) A stanchion or post of wood or iron, with two arms
      for supporting a boom, spare yards, etc.; -- called also
      crane and crutch. --Totten.
      [1913 Webster]

   3. (Billiards) In the three-ball carom game, a small space at
      each corner of the table. See Crotched, below.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

crutch
    n 1: a wooden or metal staff that fits under the armpit and
         reaches to the ground; used by disabled person while
         walking
    2: anything that serves as an expedient; "he uses drugs as a
       psychological crutch"

Moby Thesaurus II by Grady Ward, 1.0:

84 Moby Thesaurus words for "crutch":
   Malacca cane, V, advocate, alpenstock, arm, athletic supporter,
   back, backbone, backing, bandeau, baton, bearer, bra, brace,
   bracer, bracket, branch, brassiere, buttress, cane, carrier,
   cervix, corset, crook, crosier, cross, cross-staff, crotch,
   crutch-stick, delta, fan, fork, foundation garment, fulcrum,
   furcula, furculum, girdle, groin, guy, guywire, handstaff, inguen,
   jock, jockstrap, lituus, mainstay, maintainer, mast, neck,
   offshoot, pastoral staff, paterissa, prong, prop, quarterstaff,
   ramification, reinforce, reinforcement, reinforcer, rest,
   resting place, rigging, shillelagh, shoulder, shroud, spine, sprit,
   staff, standing rigging, stave, stay, stem, stick, stiffener,
   strengthener, support, supporter, sustainer, swagger stick,
   swanking stick, trident, upholder, walking stick, wishbone