\De*lir"i*um\, n. [L., fr. delirare to rave, to wander
in mind, prop., to go out of the furrow in plowing; de- +
lira furrow, track; perh. akin to G. geleise track, rut, and
E. last to endure.]
1. (Med.) A state in which the thoughts, expressions, and
   actions are wild, irregular, and incoherent; mental
   aberration; a roving or wandering of the mind, -- usually
   dependent on a fever or some other disease, and so
   distinguished from mania, or madness.
2. Strong excitement; wild enthusiasm; madness.
         The popular delirium [of the French Revolution] at
         first caught his enthusiastic mind.   --W. Irving.
         The delirium of the preceding session (of
         Parliament).                          --Morley.
{Delirium tremens}. [L., trembling delirium] (Med.), a
   violent delirium induced by the excessive and prolonged
   use of intoxicating liquors.
{Traumatic delirium} (Med.), a variety of delirium following
   injury.
Syn: Insanity; frenzy; madness; derangement; aberration;
     mania; lunacy; fury. See {Insanity}.