Possible German teetotaller getting in a couple of rounds (4)
I believe the answer is:
otto
'possible german' is the definition.
(Otto is a common German name)
'teetotaller getting in a couple of rounds' is the wordplay.
'teetotaller' becomes 'tt' (abbreviation).
'getting in' indicates putting letters inside.
'a couple of rounds' becomes 'OO' (round can mean a round object like an O).
'tt' placed into 'oo' is 'OTTO'.
(Other definitions for otto that I've seen before include "Reversible German" , "Rose produces this" , "Possibly a German" , "perfume maker" , "____ Preminger, US film director born in Austria" .)