Meaning of powder-down in English:

powder-down

Pronunciation /ˈpaʊdədaʊn/

noun

Ornithology
  • A down feather which grows continuously and disintegrates into a powder at the tips instead of being moulted (more fully "powder-down feather"); such feathers collectively, which occur in patches on certain birds, as herons, toucans, parrots, and bowerbirds, the powder being used in cleaning the plumage.

Origin

Mid 19th century; earliest use found in Proceedings of the Zoological Society of London. From powder + down, after German Puder-dune from Puder (from French poudre) + Dune, variant of Daune.