The Collaborative International Dictionary of English v.0.48:

Knee \Knee\ (n[=e]), n. [OE. kne, cneo, As. cne['o], cne['o]w;
   akin to OS. knio, kneo, OFries. kn[imac], G. & D. knie, OHG.
   chniu, chneo, Icel. kn[=e], Sw. kn[aum], Dan. kn[ae], Goth.
   kniu, L. genu, Gr. go`ny, Skr. j[=a]nu, [root]231. Cf.
   Genuflection.]
   1. In man, the joint in the middle part of the leg.
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   2. (Anat.)
      (a) The joint, or region of the joint, between the thigh
          and leg.
      (b) In the horse and allied animals, the carpal joint,
          corresponding to the wrist in man.
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   3. (Mech. & Shipbuilding) A piece of timber or metal formed
      with an angle somewhat in the shape of the human knee when
      bent.
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   4. A bending of the knee, as in respect or courtesy.
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            Give them title, knee, and approbation. --Shak.
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   Knee breeches. See under Breeches.

   Knee holly, Knee holm (Bot.), butcher's broom.

   Knee joint. See in the Vocabulary.

   Knee timber, timber with knees or angles in it.

   Knee tribute, or Knee worship, tribute paid by kneeling;
      worship by genuflection. [Obs.] "Knee tribute yet unpaid."
      --Milton.
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