The Collaborative International Dictionary of English v.0.48:

dollhouse \dollhouse\ n.
   1. a house so small that it is likened to a child's
      dollhouse. Sometimes used in reference to a small house
      with especially elaborate exterior decoration.
      [WordNet 1.5 +PJC]

   2. a small model of a house used as a toy by children,
      usually including miniature furniture and other objects
      that can be arranged inside it as the would be in a real
      house.
      [WordNet 1.5 +PJC]

WordNet (r) 3.0 (2006):

dollhouse
    n 1: a house so small that it is likened to a child's plaything
         [syn: dollhouse, doll's house]
    2: a small model of a house used as a toy by children [syn:
       dollhouse, doll's house]

Moby Thesaurus II by Grady Ward, 1.0:

54 Moby Thesaurus words for "dollhouse":
   agate, ball, baseball bat, bat, battledore, bauble, blocks,
   checkerboard, chessboard, club, cockhorse, cricket bat, cubby,
   cubbyhole, cue, doghouse, doll, doll carriage, gewgaw, gimcrack,
   golf club, hobbyhorse, hole, jack-in-the-box, jacks, jackstones,
   jackstraws, kickshaw, knickknack, marble, marionette, mig,
   paper doll, pick-up sticks, pigeonhole, pinch, pinwheel, playhouse,
   plaything, puppet, racket, rag doll, rocking horse, sport, steelie,
   taw, teetotum, tight spot, tight squeeze, top, toy, toy soldier,
   trinket, whim-wham