adjective, plum·i·er, plum·i·est.
Examples from the Web for plumy
Only near the shore were groves of cocoa-palms waving their plumy banners to the soft trade breezes.A Modern Buccaneer|Rolf Boldrewood
In my picture, half of the swans are a plumy raft for her, and row her through the air with their sweeping wings.
The feathery bamboo, most gigantic of grasses, runs in plumy lines across the country.
Another, teetering high on the plumy crest of a shadowing elm, was emptying its heart of melody.Cursed|George Allan England
The day was a brave one; the sky was stuffed with plumy clouds and the rich colors of a reverberating sunset.Melomaniacs|James Huneker