Merriam-Webster Collegiate Dictionary - plume

 I. noun  Etymology: Middle English, from Anglo-French, from Latin pluma small soft feather — more at fleece  Date: 14th century  1. a feather of a bird: as  a. a large conspicuous or showy feather  b. contour feather  c. plumage  d. a cluster of distinctive feathers  2.  a. material (as a feather, cluster of feathers, or a tuft of hair) worn as an ornament  b. a token of honor or prowess ; prize  3. something resembling a feather (as in shape, appearance, or lightness): as  a. a plumose appendage of a plant  b. an elongated and usually open and mobile column or band (as of smoke, exhaust gases, or blowing snow)  c. an animal structure having a main shaft bearing many hairs or filamentous parts; especially a full bushy tail  d. any of several columns of molten rock rising from the earth's lower mantle that are theorized to drive tectonic plate movement and to underlie hot spots  II. transitive verb  (~d; pluming)  Date: 15th century  1.  a. to provide or deck with feathers  b. to array showily  2. to indulge (oneself) in pride with an obvious or vain display of self-satisfaction  3. of a bird  a. to preen and arrange the feathers of (itself)  b. to preen and arrange (feathers)