For the poet, it's not all over (3)
I believe the answer is:
oer
'over' is the definition.
(synonyms)
'for the poet it's not all' is the wordplay.
I cannot really understand how this works, but
'not' could be 'o' (I've seen this in other clues) and 'o' is found in the answer.
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is found in the answer.
A single letter 'r' remains which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for oer that I've seen is " Above (poetic)".)