The Collaborative International Dictionary of English v.0.48:

Intermission \In`ter*mis"sion\, n. [L. intermissio: cf. F.
   intermission. See Intermit.]
   [1913 Webster]
   1. The act or the state of intermitting; the state of being
      neglected or disused; disuse; discontinuance. --B. Jonson.
      [1913 Webster]

   2. Cessation for a time; an intervening period of time; an
      interval; a temporary pause; as, to labor without
      intermission; an intermission of ten minutes.
      [1913 Webster]

            Rest or intermission none I find.     --Milton.
      [1913 Webster]

   3. Specifically: The short period between acts of a play,
      concert, opera, or other public performance when the
      audience may leave their seats for refreshment; -- it
      usually lasts from 10 to 20 minutes.
      [PJC]

   4. (Med.) The temporary cessation or subsidence of a fever;
      the space of time between the paroxysms of a disease.
      Intermission is an entire cessation, as distinguished from
      remission, or abatement of fever.
      [1913 Webster]

   5. Intervention; interposition. [Obs.] --Heylin.

   Syn: Cessation; interruption; interval; pause; stop; rest;
        suspension. See Cessation.
        [1913 Webster]

WordNet (r) 3.0 (2006):

intermission
    n 1: the act of suspending activity temporarily
    2: a time interval during which there is a temporary cessation
       of something [syn: pause, intermission, break,
       interruption, suspension]