[1] : The Collaborative International Dictionary of English v.0.48

acetabulum \ac`etab"ulum\, n. l., a little saucer for
   vinegar, fr. acetum vinegar, fr. acere to be sour.
   1913 webster
   1. rom. antiq. a vinegar cup; socket of the hip bone; a
      measure of about one eighth of a pint, etc.
      1913 webster

   2. anat.
      a the bony cup which receives the head of the thigh
          bone.
      b the cavity in which the leg of an insect is inserted
          at its articulation with the body.
      c a sucker of the sepia or cuttlefish and related
          animals.
      d the large posterior sucker of the leeches.
      e one of the lobes of the placenta in ruminating
          animals.
          1913 webster

[2] : WordNet (r) 2.0

acetabulum
     n : the cup-shaped hollow in the hipbone into which the head of
         the femur fits to form a ball-and-socket joint syn: cotyloid
         cavity
     also: acetabula pl
see also:
cotyloid cavity acetabula 

Acetabulum >> A Words
Acetabulum, definition of term: Acetabulum
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