Source : Webster's Revised Unabridged Dictionary (1913)

Interval \In"ter*val\, n. [L. intervallum; inter between +
   vallum a wall: cf. F. intervalle. See {Wall}.]
   1. A space between things; a void space intervening between
      any two objects; as, an interval between two houses or
      hills.

            'Twixt host and host but narrow space was left, A
            dreadful interval.                    --Milton.

   2. Space of time between any two points or events; as, the
      interval between the death of Charles I. of England, and
      the accession of Charles II.

   3. A brief space of time between the recurrence of similar
      conditions or states; as, the interval between paroxysms
      of pain; intervals of sanity or delirium.

   4. (Mus.) Difference in pitch between any two tones.

   {At intervals}, coming or happening with intervals between;
      now and then. ``And Miriam watch'd and dozed at
      intervals.'' --Tennyson.

   {Augmented interval} (Mus.), an interval increased by half a
      step or half a tone.

Interval \In"ter*val\, Intervale \In"ter*vale\, n.
   A tract of low ground between hills, or along the banks of a
   stream, usually alluvial land, enriched by the overflowings
   of the river, or by fertilizing deposits of earth from the
   adjacent hills. Cf. {Bottom}, n., 7. [Local, U. S.]

         The woody intervale just beyond the marshy land. --The
                                                  Century.

Source : WordNet®

interval
     n 1: a definite length of time marked off by two instants [syn: {time
          interval}]
     2: a set containing all points (or all real numbers) between
        two given endpoints
     3: the distance between things; "fragile items require
        separation and cushioning" [syn: {separation}]
     4: the difference in pitch between two notes [syn: {musical
        interval}]