Admit first wife's leaving to find sensual pleasure (5)
I believe the answer is:
allow
'admit' is the definition.
(allowing is a kind of admiting)
'first wife's leaving to find sensual pleasure' is the wordplay.
I cannot quite see how this works, but
'first' could be 'low' (synonyms) and 'low' is found in the answer.
The remaining letters 'al' is a valid word 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?
(Other definitions for allow that I've seen before include "brook" , "Give leave to" , "Admit as acceptable" , "Permit or concede" , "Permit or agree" .)