Managed company move, mostly acrimonious (9)
I believe the answer is:
rancorous
'acrimonious' is the definition.
(synonyms)
'managed company move mostly' is the wordplay.
'managed' becomes 'ran' (both can mean organised or was in charge of).
'company' becomes 'co' (abbreviation).
'move mostly' becomes 'rous' (I can't justify this - if you can you should believe this answer much more).
'ran'+'co'+'rous'='RANCOROUS'
Can you help me to learn more?
(Other definitions for rancorous that I've seen before include "spiteful?" , "Acrimonious" , "Resentful, bitter" , "Showing bitter resentment" .)