|1.||a circular pleated, gathered, or fluted collar of lawn, muslin, etc, often starched or wired, worn by both men and women in the 16th and 17th centuries|
|2.||zoology a natural growth of long or coloured hair or feathers around the necks of certain animals or birds|
|3.||a. an Old World shore bird, Philomachus pugnax, the male of which has a large erectile ruff of feathers in the breeding season: family Scolopacidae (sandpipers, etc), order Charadriiformes|
|b. Compare reeve the male of this bird|
|[C16: back formation from |
in zoology, Old World bird (Philomachus pugnax), of the sandpiper subfamily Calidritinae (family Scolopacidae) remarkable for its courtship plumage and behaviour. The name ruff applies to the species or may be applied to the male only. In spring the 30-centimetre (12-inch) male acquires a double crest ("cape") and a collar ("ruff"); these may contain reddish, brown, black, and white feathers in proportions that vary with the individual (the most extreme case of polymorphism known among birds). The female, called the reeve, is only about 25 centimetres (10 inches) long and is plain grayish brown, as is the male in winter. In the breeding season males gather on a traditional display area (lek), usually a bare hill, and, while the reeves watch, display close together by making short rushes with cape and ruff erect and wings drooping. When a reeve strolls into their midst the males collapse, quivering, with bills stuck into the ground. Then the female chooses one of the males. She builds a nest, incubates the eggs, and raises the chicks alone. The sexes keep apart, even in flocks (further evidence of the extreme dimorphism of the species)
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