Resists posies I left after work (7)
I believe the answer is:
opposes
'resists' is the definition.
(I've seen this in another clue)
'posies i left after work' is the wordplay.
'left' suggests deleting specific letters (some letters have left).
'after' means one lot of letters go next to another.
'work' becomes 'op' (common abbreviation for 'opus').
'posies' with 'i' taken out is 'poses'.
'poses' put after 'op' is 'OPPOSES'.
(Other definitions for opposes that I've seen before include "Disagrees with and attempts to prevent" , "Stands against" , "Counters" , "Strongly disapproves" , "Goes against" .)