Subjugate; subdue (7)
I believe the answer is:
oppress
This clue is a double definition.
'subjugate' is the first definition.
(I've seen this in another clue)
'subdue' is the second definition.
(I've seen this before)
(Other definitions for oppress that I've seen before include "Treat tyrannically" , "Cause to suffer" , "Torment" , "'Persecute, come down heavy on (7)'" , "Distress" .)