Source : Webster's Revised Unabridged Dictionary (1913)

Beat \Beat\, n.
   1. A stroke; a blow.

            He, with a careless beat, Struck out the mute
            creation at a heat.                   --Dryden.

   2. A recurring stroke; a throb; a pulsation; as, a beat of
      the heart; the beat of the pulse.

   3. (Mus.)
      (a) The rise or fall of the hand or foot, marking the
          divisions of time; a division of the measure so
          marked. In the rhythm of music the beat is the unit.
      (b) A transient grace note, struck immediately before the
          one it is intended to ornament.

   4. (Acoustics & Mus.) A sudden swelling or re["e]nforcement
      of a sound, recurring at regular intervals, and produced
      by the interference of sound waves of slightly different
      periods of vibrations; applied also, by analogy, to other
      kinds of wave motions; the pulsation or throbbing produced
      by the vibrating together of two tones not quite in
      unison. See {Beat}, v. i., 8.

   5. A round or course which is frequently gone over; as, a
      watchman's beat.

   6. A place of habitual or frequent resort.

   7. A cheat or swindler of the lowest grade; -- often
      emphasized by dead; as, a dead beat. [Low]

   {Beat of drum} (Mil.), a succession of strokes varied, in
      different ways, for particular purposes, as to regulate a
      march, to call soldiers to their arms or quarters, to
      direct an attack, or retreat, etc.

   {Beat of a watch}, or {clock}, the stroke or sound made by
      the action of the escapement. A clock is in beat or out of
      beat, according as the strokes is at equal or unequal
      intervals.