noun (n)

• (electronics) a sharp transient wave in the normal electrical state (or a series of such transients)(noun.event)

  Example:
  The pulsations seemed to be coming from a star.
  

  Synonym:
  impulse, pulse, pulsing
  

  source: wordnet30
• a periodically recurring phenomenon that alternately increases and decreases some quantity(noun.phenomenon)

  source: wordnet30
• the rhythmic contraction and expansion of the arteries with each beat of the heart(noun.event)

  Synonym:
  beat, heartbeat, pulse
  

  source: wordnet30
• A beating or throbbing, especially of the heart or of an artery, or in an inflamed part; a beat of the pulse.(noun)

  source: webster1913