Baffle loud and clumsy oaf (7)
I believe the answer is:
flummox
'baffle' is the definition.
('flummox' can be a synonym of 'baffle')
'loud and clumsy oaf' is the wordplay.
'loud' becomes 'f' (A musical term).
'and' says to put letters next to each other.
'clumsy oaf' becomes 'lummox' (I've seen this before).
'f'+'lummox'='FLUMMOX'
(Other definitions for flummox that I've seen before include "Baffle" , "'Confuse, bewilder (7)'" , "Puzzle" , "Perplex" , "Nonplus" .)