The Collaborative International Dictionary of English v.0.48:
Plume \Plume\, n. [F., fr. L. pluma. Cf. Fly, v.]
1. A feather; esp., a soft, downy feather, or a long,
conspicuous, or handsome feather.
Wings . . . of many a colored plume. --Milton.
2. (Zool.) An ornamental tuft of feathers.
3. A feather, or group of feathers, worn as an ornament; a
waving ornament of hair, or other material resembling
His high plume, that nodded o'er his head. --Dryden.
4. A token of honor or prowess; that on which one prides
himself; a prize or reward. "Ambitious to win from me some
5. (Bot.) A large and flexible panicle of inflorescence
resembling a feather, such as is seen in certain large
Plume bird (Zool.), any bird that yields ornamental plumes,
especially the species of Epimarchus from New Guinea, and
some of the herons and egrets, as the white heron of
Florida (Ardea candidissima).
Plume grass. (Bot)
(a) A kind of grass (Erianthus saccharoides) with the
spikelets arranged in great silky plumes, growing in
swamps in the Southern United States.
(b) The still finer Erianthus Ravenn[ae] from the
Mediterranean region. The name is sometimes extended
to the whole genus.
Plume moth (Zool.), any one of numerous small, slender
moths, belonging to the family Pterophorid[ae]. Most of
them have the wings deeply divided into two or more
plumelike lobes. Some species are injurious to the
Plume nutmeg (Bot.), an aromatic Australian tree
(Atherosperma moschata), whose numerous carpels are
tipped with long plumose persistent styles.