Plait of hair (5)
I believe the answer is:
tress
'plait of hair' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for tress that I've seen before include "is a bit of a shock" , "Long lock or plait of hair" , "Rests (anag.)" , "Bit of hair" , "Obsolete support" .)