Source : Webster's Revised Unabridged Dictionary (1913)

Hoot \Hoot\, n.
   1. A derisive cry or shout. --Glanvill.

   2. The cry of an owl.

   {Hoot owl} (Zo["o]l.), the barred owl ({Syrnium nebulosum}).
      See {Barred owl}.

Source : WordNet®

hoot owl
     n : any owl that hoots as distinct from screeching