At home, chap is cold (9)
I believe the answer is:
inclement
'is cold' is the definition.
(thesaurus)
'at home chap' is the wordplay.
'at home' becomes 'in' ('I'm in' can mean 'I'm at home').
'chap' becomes 'clement' ().
'in'+'clement'='INCLEMENT'
(Other definitions for inclement that I've seen before include "lacking mercy" , "not fair" , "(Of weather) bad" , "bitter" , "Such harsh weather" .)