Source : Webster's Revised Unabridged Dictionary (1913)

Utility \U*til"i*ty\, n. [OE. utilite, F. utilit['e], L.
   utilitas, fr. utilis useful. See {Utile}.]
   1. The quality or state of being useful; usefulness;
      production of good; profitableness to some valuable end;
      as, the utility of manure upon land; the utility of the
      sciences; the utility of medicines.

            The utility of the enterprises was, however, so
            great and obvious that all opposition proved
            useless.                              --Macaulay.

   2. (Polit. Econ.) Adaptation to satisfy the desires or wants;
      intrinsic value. See Note under {Value}, 2.

            Value in use is utility, and nothing else, and in
            political economy should be called by that name and
            no other.                             --F. A.
                                                  Walker.

   3. Happiness; the greatest good, or happiness, of the
      greatest number, -- the foundation of utilitarianism. --J.
      S. Mill.

   Syn: Usefulness; advantageous; benefit; profit; avail;
        service.

   Usage: {Utility}, {Usefulness}. Usefulness has an Anglo-Saxon
          prefix, utility is Latin; and hence the former is used
          chiefly of things in the concrete, while the latter is
          employed more in a general and abstract sense. Thus,
          we speak of the utility of an invention, and the
          usefulness of the thing invented; of the utility of an
          institution, and the usefulness of an individual. So
          beauty and utility (not usefulness) are brought into
          comparison. Still, the words are often used
          interchangeably.

Source : WordNet®

utility
     adj 1: used of beef; usable but inferior [syn: {utility(a)}, {utility-grade}]
     2: capable of substituting in any of several positions on a
        team; "a utility infielder" [syn: {utility(a)}, {substitute(a)}]

utility
     n 1: a company that performs a public service; subject to
          government regulation [syn: {public utility}, {public-service
          corporation}]
     2: the quality of being of practical use [syn: {usefulness}]
        [ant: {inutility}, {inutility}]
     3: the service provided by a utility company; "the cost of
        utilities never decreases"
     4: (economics) a measure that is to be maximized in any
        situation involving choice
     5: (computer science) a program designed for general support of
        the processes of a computer; "a computer system provides
        utility programs to perform the tasks needed by most
        users" [syn: {utility program}, {service program}]
     6: a facility composed of one or more pieces of equipment
        connected to or part of a structure and designed to
        provide a service such as heat or electricity or water or
        sewage disposal; "the price of the house included all
        utilities"