After which it is no longer a dirty wet suit? (3,8)

'dirty wet suit?' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Perhaps there's a link between them I don't understand?

'after which it is no longer a' is the wordplay.
I cannot quite understand how this works, but
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is located in the answer.
'no' could be 'n' (common abbreviation) and 'n' is found in the answer.
'a' is within the answer.
'after which' could be 'i' (I've seen this in other clues) and 'i' is found within the answer.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?