Get cosy (6)
I believe the answer is:
nestle
'get cosy' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for nestle that I've seen before include "Cuddle into soft place" , "Be snug as a baby bird" , "Cuddle up, like bird in bed?" , "Lie snugly (in a place)" , "Cuddle closely" .)