Cut complaint that's expressed (4)
I believe the answer is:
mown
'cut' is the definition.
(synonyms)
'complaint that's expressed' is the wordplay.
'complaint' becomes 'moan' (I've seen this before).
'that's expressed' indicates a 'sounds like' (homophone) clue.
'moan' sounds like 'MOWN'.
(Other definitions for mown that I've seen before include "Block of cast metal" , "Cut down with a blade" , "(Of grass) cut" .)