Put on warm clothes (4,2)
I believe the answer is:
wrap up
'put on warm clothes' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for wrap up that I've seen before include "Be quiet - fold paper round - finish" , "put a sock in it" , "Keep warm" , "Wear warm garment" , "Stop talking and put on warm clothing" .)