Source : Webster's Revised Unabridged Dictionary (1913)

Stimulation \Stim`u*la"tion\, n. [L. stimulatio: cf. F.
   stimulation.]
   1. The act of stimulating, or the state of being stimulated.

   2. (Physiol.) The irritating action of various agents
      (stimuli) on muscles, nerves, or a sensory end organ, by
      which activity is evoked; especially, the nervous impulse
      produced by various agents on nerves, or a sensory end
      organ, by which the part connected with the nerve is
      thrown into a state of activity; irritation.

Source : WordNet®

stimulation
     n 1: the act of arousing an organism to action
     2: any stimulating information or event; acts to arouse action
        [syn: {stimulus}, {stimulant}, {input}]
     3: (physiology) the effect of a stimulus (on nerves or organs
        etc.)
     4: mutual sexual stimulation prior to sexual intercourse [syn:
        {foreplay}, {arousal}]