1 a cloud of sth that rises and curves upwards in the air:
a plume of smoke * A radioactive plume could reach the city within hours.
2 a large feather:
a black hat with an ostrich plume
3 a group of feathers or long thin pieces of material tied together and often used as a decoration:
The red plume on the horse's head was nodding to the rhythm of its steps.
seealsoNOMDEPLUME
