What is "gray duck"

Pintail \Pin"tail`\, n.

1. (Zo["o]l.) A northern duck ( Dafila acuta), native of both continents. The adult male has a long, tapering tail. Called also gray duck, piketail, piket-tail, spike-tail, split-tail, springtail, sea pheasant, and gray widgeon.

2. (Zo["o]l.) The sharp-tailed grouse of the great plains and Rocky Mountains ( Pedioc[ae]tes phasianellus); -- called also pintailed grouse, pintailed chicken, springtail, and sharptail.

Gadwall \Gad"wall\, n. [Gad to walk about + well.] (Zo["o]l.) A large duck ( Anas strepera), valued as a game bird, found in the northern parts of Europe and America; -- called also gray duck. [Written also gaddwell.]