Plumule

n.	1.	(Bot.) The first bud, or gemmule, of a young plant; the bud, or growing point, of the embryo, above the cotyledons. See Illust. of Radicle.
	2.	(Zool.) A down feather.

Noun

1.

plumule - down feather of young birds; persists in some adult birds

down, down feather