Senior manager's allowance producing hatred (10)
I believe the answer is:
execration
'hatred' is the definition.
(I know that execration is a type of hatred)
'senior manager's allowance' is the wordplay.
'senior manager' becomes 'exec' (short for executive).
'allowance' becomes 'ration' (I've seen this before).
'exec'+'ration'='EXECRATION'
'producing' is the link.
(Other definitions for execration that I've seen before include "Violent disapproval" , "serious stick" , "denunciation" , "Cursing" .)