The Collaborative International Dictionary of English v.0.48:

Manikin \Man"i*kin\, n. [Also spelled mannikin.] [OD.
   manneken, dim. of man man. See Man, and -kin.]
   1. A little man; a dwarf; a pygmy; a manakin.
      [1913 Webster]

   2. A model of the human body, made of papier-mache or other
      material, commonly in detachable pieces, for exhibiting
      the different parts and organs, their relative position,
      etc.
      [1913 Webster]

   3. A mannequin.
      [PJC] Manila

WordNet (r) 3.0 (2006):

manikin
    n 1: a person who is very small but who is not otherwise
         deformed or abnormal [syn: manikin, mannikin,
         homunculus]
    2: a woman who wears clothes to display fashions; "she was too
       fat to be a mannequin" [syn: mannequin, manikin,
       mannikin, manakin, fashion model, model]
    3: a life-size dummy used to display clothes [syn: mannequin,
       manikin, mannikin, manakin, form]