Suppress, to remain on good terms with (4,2)
I believe the answer is:
keep in
'suppress' is the definition.
(thesaurus)
'remain on good terms with' is the wordplay.
I cannot quite see how this works, but
'remain' could be 'keep' (keeping is a kind of remaining) and 'keep' is found in the answer.
The remaining letters 'in' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'to' is the link.
Can you help me to learn more?
(Other definitions for keep in that I've seen before include "Conceal" , "Restrain" , "Contain" , "punish a pupil" , "Bottle up - shut up" .)