Source : Webster's Revised Unabridged Dictionary (1913)

Sedation \Se*da"tion\, n. [L. sedatio.]
   The act of calming, or the state of being calm. [R.] --Coles.

Source : WordNet®

sedation
     n 1: a state of reduced excitement or anxiety that is induced by
          the administrative of a sedative agent
     2: the administration of a sedative agent or drug [syn: {drugging}]