Sits after work and resists (7)
I believe the answer is:
opposes
'resists' is the definition.
(I've seen this in another clue)
'sits after work' is the wordplay.
'sits' becomes 'poses' ('pose' can be a synonym of 'sit').
'after' says to put letters next to each other.
'work' becomes 'op' (abbreviation for opus).
'poses' after 'op' is 'OPPOSES'.
'and' acts as a link.
(Other definitions for opposes that I've seen before include "Counters" , "Disagrees with and attempts to prevent" , "Goes against" , "Strongly disapproves" , "Stands against" .)