Resisted work: assumed an attitude (7)
I believe the answer is:
opposed
'resisted' is the definition.
(I've seen this before)
'work assumed an attitude' is the wordplay.
I cannot really understand how this works, but
'work' could be 'op' (common abbreviation for 'opus') and 'op' is found within the answer.
'assumed' could be 'posed' (I've seen this before) and 'posed' is present in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for opposed that I've seen before include "Resisted" , "Anti" , "Stood against" , "like foes" , "likely to refuse?" .)