Screamer \Scream"er\, n. (Zo["o]l.) Any one of three species of South American birds constituting the family Anhimid[ae], and the suborder Palamede[ae]. 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.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Screamer \Scream"er\, n.

1. Something so remarkable as to provoke a scream, as of joy. [Slang]

2. An exclamation mark. [Printer's Slang]

Source: Webster's Revised Unabridged Dictionary (1913)