As ports go, not a good one? (6)
I believe the answer is:
abadan
'as ports go not a' is the definition.
I can't tell whether this defines the answer.
'good one?' is the wordplay.
'good' becomes 'abad' (I can't explain this - if you can you should give a lot more credence to this answer).
'one?' becomes 'an' (an apple is one apple).
'abad'+'an'='ABADAN'
Can you help me to learn more?
(Other definitions for abadan that I've seen before include "African capital" , "in Iran" , "oil-refining place" , "foreign port" .)