Game partners try turning over to canoodle (4)
I believe the answer is:
snog
'canoodle' is the definition.
(to canoodle is to kiss and cuddle)
'game partners try turning over' is the wordplay.
'game partners' becomes 'sn' (South and North are team mates in the game bridge).
'try' becomes 'go' (go is a kind of try).
'turning over' says the letters should be written in reverse.
'go' in reverse letter order is 'og'.
'sn'+'og'='SNOG'
'to' acts as a link.
(Other definitions for snog that I've seen before include "Pet" , "Kiss and cuddle (sl.)" , "Cuddle, kiss (slang)" , "Amorously kiss" , "Indulge in amorous activity" .)