pintail

noun, plural pin·tails, (especially collectively) pin·tail.

1. a long-necked river duck, Anas acuta, of the Old and New Worlds, having long and narrow middle tail feathers.
2. sharp-tailed grouse.

noun plural -tails or -tail

1. a greyish-brown duck, Anas acuta, with slender pointed wings and a pointed tail

n.type of duck, 1767, from pin (n.1) + tail (n.).