The Collaborative International Dictionary of English v.0.48:

Delirious \De*lir"i*ous\, a. [From Delirium.]
   Having a delirium; wandering in mind; light-headed; insane;
   raving; wild; as, a delirious patient; delirious fancies. --
   De*lir"i*ous*ly, adv. -- De*lir"i*ous*ness, n.
   [1913 Webster]