Could it help keep one's chest a bit warm in bed? (5)
I believe the answer is:
beard
'could it help keep one's chest a bit' is the definition.
I can't tell whether this definition defines the answer.
'warm in bed?' is the wordplay.
'warm' becomes 'ar' (I can't explain this - if you can you should believe this answer much more).
'in' is an insertion indicator.
'ar' put into 'bed' is 'BEARD'.
Can you help me to learn more?
(Other definitions for beard that I've seen before include "In good health; very" , "where food sometimes trapped?" , "Boldly confront (formidable opponent)" , "Goatee, for instance" , "Oppose with effrontery" .)