The Collaborative International Dictionary of English v.0.48:

Acclimate \Ac*cli"mate\ (#; 277), v. t. [imp. & p. p.
   Acclimated; p. pr. & vb. n. Acclimating.] [F. acclimater;
   [`a] (l. ad) + climat climate. See Climate.]
   To habituate to a climate not native; to acclimatize. --J. H.
   Newman.
   [1913 Webster]

WordNet (r) 3.0 (2006):

acclimate
    v 1: get used to a certain climate; "They never acclimatized in
         Egypt" [syn: acclimatize, acclimatise, acclimate]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "acclimate":
   acclimatize, accommodate, accustom, adapt, adjust, break, break in,
   case harden, condition, confirm, domesticate, domesticize,
   establish, familiarize, fix, gentle, habituate, harden, housebreak,
   inure, naturalize, orient, orientate, season, tame, toughen, train,
   wont