The Collaborative International Dictionary of English v.0.48:

Tirade \Ti*rade"\, n. [F., fr. It. tirada, properly, a pulling;
   hence, a lengthening out, a long speech, a tirade, fr. tirare
   to draw; of Teutonic origin, and akin to E. tear to redn. See
   Tear to rend, and cf. Tire to tear.]
   A declamatory strain or flight of censure or abuse; a
   rambling invective; an oration or harangue abounding in
   censorious and bitter language.
   [1913 Webster]

         Here he delivers a violent tirade against persons who
         profess to know anything about angels.   --Quarterly
                                                  Review.
   [1913 Webster]

WordNet (r) 3.0 (2006):

tirade
    n 1: a speech of violent denunciation [syn: tirade,
         philippic, broadside]