The Collaborative International Dictionary
Filoplume
Filoplume \Fil"o*plume\, n. [L. filum a thread ? pluma a soft feather.] (Zo["o]l.) A hairlike feather; a father with a slender scape and without a web in most or all of its length.
Wiktionary
filoplume
n. (context zoology English) A hair-like feather; a feather with a slender scape and without a web in most or all of its length.