The Collaborative International Dictionary of English v.0.48:

Rant \Rant\ (r[a^]nt), v. i. [imp. & p. p. Ranted; p. pr. &
   vb. n. Ranting.] [OD. ranten, randen, to dote, to be
   enraged.]
   To rave in violent, high-sounding, or extravagant language,
   without dignity of thought; to be noisy, boisterous, and
   bombastic in talk or declamation; as, a ranting preacher.
   [1913 Webster]

         Look where my ranting host of the Garter comes! --Shak.
   [1913 Webster]

WordNet (r) 3.0 (2006):

ranting
    n 1: a loud bombastic declamation expressed with strong emotion
         [syn: harangue, rant, ranting]