from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Either of two diving ducks (Aythya marila or A. affinis) having predominantly black and white plumage in the male. Also called bluebill.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of three species of small diving duck in the genus Aythya.
- n. Alternative form of scalp; a bed or stratum of shellfish.
from the GNU version of the Collaborative International Dictionary of English
- n. A bed or stratum of shellfish; scalp.
- n. A scaup duck. See below.
from The Century Dictionary and Cyclopedia
- n. A Scotch form of scalp.
- n. A duck, Fuligula or Fulix marila and related species.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. diving ducks of North America having a bluish-grey bill
Perhaps from Scots scalp, scaup, bed of mussels (from its feeding on shellfish).(American Heritage® Dictionary of the English Language, Fourth Edition)
See scalp ("a bed of oysters or mussels"). (Wiktionary)