Legal document about job largely is removed from office (7)
I believe the answer is:
deposed
'removed from office' is the definition.
(I've seen this before)
'legal document about job largely' is the wordplay.
'legal document' becomes 'deed' (deed is a kind of legal document**).
'about' indicates putting letters inside.
'job' becomes 'post' (post is a kind of job).
'largely' means to remove the last letter.
'post' with its last letter taken off is 'pos'.
'deed' enclosing 'pos' is 'DEPOSED'.
'is' acts as a link.
(Other definitions for deposed that I've seen before include "Forced out of office or power" , "Thrown out" , "Forcibly removed from office" .)