fluff

n. 软毛,柔毛,绒毛

Clinging bits of fiber and fluff; fuzz.

棉绒，软棉布聚在一起的纤维和绒毛；细毛

Courtship will include display in which the male fluff up his feather.

鸟儿求偶的表现包括雄鸟抖松羽毛的炫耀行为。