Down feather
SOFT, FINE FEATHER, SOMETIMES UNDER LARGER FEATHERS
Powder down; Bird down; Duck down; Down feathers; Down (feather); Neoptile; Neossoptile; Nessoptile; Feather dust; Natal down; Body down; Plumaceous; Powderdown; Powder-down feather; Pulviplume; Plumule (zoology); Goose down; Plumulaceous feather; Plumulaceous
The down of birds is a layer of fine feathers found under the tougher exterior feathers. Very young birds are clad only in down.