1. A feather, especially a large and showy one.
2. A large feather or cluster of feathers worn as an ornament or symbol of rank, as on a helmet.
3. A token of honor or achievement.4. A structure or form that is like a long feather: a plume of smoke.
5. Ecology A space in air, water, or soil containing pollutants released from a point source.
6. Geology An upwelling of molten material from the earth's mantle.
tr.v. plumed, plum·ing, plumes
1. To decorate, cover, or supply with or as if with plumes.
2. To smooth (feathers); preen.
3. To congratulate (oneself) in a self-satisfied way: plumed himself on his victory.plume - definition of plume by the Free Online Dictionary, Thesaurus and Encyclopedia.