The Collaborative International Dictionary
Ring-necked \Ring"-necked`\, a. (Zo["o]l.) Having a well defined ring of color around the neck.
Ring-necked duck (Zool.), an American scaup duck ( Aythya collaris). The head, neck, and breast of the adult male are black, and a narrow, but conspicuous, red ring encircles the neck. This ring is absent in the female. Called also ring-neck, ring-necked blackhead, ringbill, tufted duck, and black jack.
Wiktionary
n. A species of duck, ''(l mul Aythya fuligula)''.
Wikipedia
The Tufted duck (Aythya fuligula) is a small diving duck with a population of close to one million birds. The scientific name is derived from Ancient Greek '' aithuia'' an unidentified seabird mentioned by authors including Hesychius and Aristotle, and Latin, fuligo "soot" and gula "throat".
Usage examples of "tufted duck".
There was indeed a splendid wealth of birds on the water, including some very, very old friends such as wigeon, tufted duck, mallard and shoveller, perfectly at home among the neat little pygmy geese, knob-billed and spur-winged geese, white-faced tree-duck and the odd anhingas, to say nothing of the blue-breasted kingfisher that darted overhead and the steady patrol of vultures in the upper sky.