Rent hill, to a point (4)
I believe the answer is:
tore
'rent' is the definition.
('rend' and 'tear' both mean to rip something)
'hill to a point' is the wordplay.
'hill' becomes 'tor' (tor is a kind of hill).
'to a point' becomes 'e' (compass point).
'tor'+'e'='TORE'
(Other definitions for tore that I've seen before include "Ripped; went fast" , "Ripped; went quickly" , "Pulled something apart forcefully" , "Ripped by rote" , "Was moving very quickly" .)