Plume's source (5)
I believe the answer is:
egret
'plume's source' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for egret that I've seen before include "one with plume" , "Kind of white heron - greet it" , "Type of heron" , "White-feathered wading bird" , "One of a pair of waders" .)