The Collaborative International Dictionary of English v.0.48:

Howl \Howl\, v. i. [imp. & p. p. Howled; p. pr. & vb. n.
   Howling.] [OE. houlen, hulen; akin to D. huilen, MHG.
   hiulen, hiuweln, OHG. hiuwil[=o]n to exult, h?wo owl, Dan.
   hyle to howl.]
   1. To utter a loud, protracted, mournful sound or cry, as
      dogs and wolves often do.
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            And dogs in corners set them down to howl.
                                                  --Drayton.
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            Methought a legion of foul fiends
            Environ'd me about, and howled in my ears. --Shak.
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   2. To utter a sound expressive of distress; to cry aloud and
      mournfully; to lament; to wail.
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            Howl ye, for the day of the Lord is at hand. --Is.
                                                  xiii. 6.
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   3. To make a noise resembling the cry of a wild beast.
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            Wild howled the wind.                 --Sir W.
                                                  Scott.
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   Howling monkey. (Zool.) See Howler, 2.

   Howling wilderness, a wild, desolate place inhabited only
      by wild beasts. --Deut. xxxii. 10.
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WordNet (r) 3.0 (2006):

howling
    adj 1: extraordinarily good or great ; used especially as
           intensifiers; "a fantastic trip to the Orient"; "the film
           was fantastic!"; "a howling success"; "a marvelous
           collection of rare books"; "had a rattling conversation
           about politics"; "a tremendous achievement" [syn:
           fantastic, grand, howling(a), marvelous,
           marvellous, rattling(a), terrific, tremendous,
           wonderful, wondrous]
    n 1: a long loud emotional utterance; "he gave a howl of pain";
         "howls of laughter"; "their howling had no effect" [syn:
         howl, howling, ululation]