This writer recalled stratagem editor used (8)
I believe the answer is:
employed
'used' is the definition.
('employ' can be a synonym of 'use')
'this writer recalled stratagem editor' is the wordplay.
'this writer' becomes 'me' (the person who wrote the clues).
'recalled' shows that the letters should be reversed in order (to recall can mean to bring something back).
'stratagem' becomes 'ploy' (synonyms).
'editor' becomes 'ed' (abbreviation).
'me' in reverse letter order is 'em'.
'em'+'ploy'+'ed'='EMPLOYED'
(Other definitions for employed that I've seen before include "Engaged - used" , "Gave work to" , "Engaged in paid work" , "Working" , "Hired, made use of" .)