Mostly ill-tempered English poet (6)
I believe the answer is:
crabbe
'english poet' is the definition.
(George Crabbe 1754-1832)
'mostly ill-tempered' is the wordplay.
'mostly' means to remove the last letter.
'ill-tempered' becomes 'crabbed' (synonyms).
'crabbed' with its last letter taken away is 'CRABBE'.
(Other definitions for crabbe that I've seen before include "George -, English poet (The Borough)" , "Buster --, US swimmer/actor" , "Village poet" , "George ---, Jane Austen's favourite poet" , "George ---, Aldeburgh poet" .)