The Collaborative International Dictionary of English v.0.48:

Excruciation \Ex*cru`ci*a"tion\n. [L. excruciatio.]
   The act of inflicting agonizing pain, or the state of being
   thus afflicted; that which excruciates; torture. --Feltham.
   [1913 Webster]

WordNet (r) 3.0 (2006):

excruciation
    n 1: a state of acute pain [syn: agony, suffering,
         excruciation]
    2: the infliction of extremely painful punishment or suffering
       [syn: crucifixion, excruciation]