Cold, boy dressed (4)
I believe the answer is:
clad
'dressed' is the definition.
(to be clad in something is to be dressed in it)
'cold boy' is the wordplay.
'cold' becomes 'c' (eg on taps).
'boy' becomes 'lad' (informal term for boy).
'c'+'lad'='CLAD'
(Other definitions for clad that I've seen before include "Attired" , "Clothed, covered" , "Decked" , "Wearing" , "in dress perhaps" .)