The Collaborative International Dictionary of English v.0.48:

Screech \Screech\, n.
   A harsh, shrill cry, as of one in acute pain or in fright; a
   shriek; a scream.
   [1913 Webster]

   Screech bird, or Screech thrush (Zool.), the fieldfare;
      -- so called from its harsh cry before rain.

   Screech rain.

   Screech hawk (Zool.), the European goatsucker; -- so called
      from its note. [Prov. Eng.]

   Screech owl. (Zool.)
   (a) A small American owl (Scops asio), either gray or
       reddish in color.
   (b) The European barn owl. The name is applied also to other
       species.
       [1913 Webster]

WordNet (r) 3.0 (2006):

screech owl
    n 1: any owl that has a screeching cry
    2: small North American owl having hornlike tufts of feathers
       whose call sounds like a quavering whistle [syn: screech
       owl, Otus asio]