Circle south, at times going by, city in Japan (5)
I believe the answer is:
osaka
'city in japan' is the definition.
(I've seen this in another clue)
'circle south at times going by' is the wordplay.
I cannot quite understand how this works, but
'circle' could be 'o' (O is a circle) and 'o' is found within the answer.
'south' could be 's' (abbreviation) and 's' is found within the answer.
'going by' could be 'aka' (I've seen this in another clue) and 'aka' is present in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for osaka that I've seen before include "Japanese port, on Honshu" , "Place" , "Asian" , "Kinki's capital" , "Large city and port in Japan" .)