The Collaborative International Dictionary of English v.0.48:

Screamer \Scream"er\ (skr[=e]m"[~e]r), n. (Zool.)
   Any one of three species of South American birds constituting
   the family Anhimidae, and the suborder Palamedeae. They
   have two spines on each wing, and the head is either crested
   or horned. They are easily tamed, and then serve as guardians
   for other poultry. The crested screamers, or chajas, belong
   to the genus Chauna. The horned screamer, or kamichi, is
   Palamedea cornuta.
   [1913 Webster]

   2. Something so remarkable as to provoke a scream, as of joy.
      [Slang]
      [Webster 1913 Suppl.]

   3. An exclamation mark. [Printer's Slang]
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

screamer
    n 1: someone who communicates vocally in a very loud voice [syn:
         roarer, bawler, bellower, screamer, screecher,
         shouter, yeller]
    2: a sensational newspaper headline
    3: gooselike aquatic bird of South America having a harsh
       trumpeting call
    4: a very hard hit ball [syn: scorcher, screamer]

The Free On-line Dictionary of Computing (19 January 2023):

Screamer

   An extension of Common Lisp providing nondeterministic
   backtracking and constraint programming.

   (ftp://ftp.ai.mit.edu/pub/screamer.tar.Z).

   [Isn't all backtracking nondeterministic by definition?]