British artist in underwear (3)
I believe the answer is:
bra
'underwear' is the definition.
(bra is a type of undergarment)
'british artist' is the wordplay.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'b'+'ra'='BRA'
'in' is the link.
(Other definitions for bra that I've seen before include "Female undergarment" , "Chest supporter" , "I give a couple a lift" , "one carrying chest" , "Underwear item" .)