The Collaborative International Dictionary of English v.0.48:

Utilize \U"til*ize\, v. t. [imp. & p. p. Utilized; p. pr. &
   vb. n. Utilizing.] [Cf. F. utiliser.]
   To make useful; to turn to profitable account or use; to make
   use of; as, to utilize the whole power of a machine; to
   utilize one's opportunities.
   [1913 Webster]

         In former ages, the mile-long corridors, with their
         numerous alcoves, might have been utilized as . . .
         dungeons.                                --Hawthorne.
   [1913 Webster]

WordNet (r) 3.0 (2006):

utilize
    v 1: put into service; make work or employ for a particular
         purpose or for its inherent or natural purpose; "use your
         head!"; "we only use Spanish at home"; "I can't use this
         tool"; "Apply a magnetic field here"; "This thinking was
         applied to many projects"; "How do you utilize this tool?";
         "I apply this rule to get good results"; "use the plastic
         bags to store the food"; "He doesn't know how to use a
         computer" [syn: use, utilize, utilise, apply,
         employ]
    2: convert (from an investment trust to a unit trust)

Moby Thesaurus II by Grady Ward, 1.0:

24 Moby Thesaurus words for "utilize":
   apply, bestow, do with, employ, exercise, exert, exploit, handle,
   make use of, manage, manipulate, operate, play, ply, practice,
   process, procure materials, promote, stock, stock up, store, use,
   wield, work