Kneepan

from WordNet (r) 3.0 (2006)

kneepan
    n 1: a small flat triangular bone in front of the knee that
         protects the knee joint [syn: {patella}, {kneecap},
         {kneepan}]

from The Collaborative International Dictionary of English v.0.48

Kneepan \Knee"pan`\, n. (Anat.)
   A roundish, flattened, sesamoid bone in the tendon in front
   of the knee joint; the patella; the kneecap.
   [1913 Webster]

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