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Webster 1913 Edition

Noun.

(Zool.)

(a)

Any one or several species of swifts of the genus

Acanthylis

, or

Chaetura

, and allied genera, in which the shafts of the tail feathers terminate in rigid spines.

(b)

Any one of several species of South American and Central American clamatorial birds belonging to

Synallaxis

and allied genera of the family

Dendrocolaptidae

. They are allied to the ovenbirds.

(c)

The ruddy duck.

[Local, U.S.]

spinetail ‎(plural spinetails)

Any of several species of swifts of Acanthylis, Chaetura, and allied genera, in which the shafts of the tail feathers terminate in rigid spines.
Any of several species of South American and Central American clamatorial birds belonging to Synallaxis and allied genera of the family Dendrocolaptidae, allied to the ovenbirds.
(US, dialect) The ruddy duck, Oxyura jamaicensis.