Friendly with member (4)
I believe the answer is:
warm
'friendly' is the definition.
('warm' is associated in meaning with 'friendly')
'with member' is the wordplay.
'with' becomes 'w' (abbreviation).
'member' becomes 'arm' (arm is a kind of member**).
'w'+'arm'='WARM'
(Other definitions for warm that I've seen before include "Intimate - with a comfortable temperature" , "Cordial" , "(Of a scent) fresh" , "Affectionate; heat" , "Tepid" .)