Counteract (6)
I believe the answer is:
offset
'counteract' is the definition.
(I know that counteract is a more specific form of the action offset)
This is the entire clue.
(Other definitions for offset that I've seen before include "Place out of line" , "Counterbalance(d)" , "Type of printing of efts" , "Amount by which a thing is out of line" , "Compensate for - printing method" .)