Tor (4)
I believe the answer is:
hill
'tor' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for hill that I've seen before include "See 14" , "Any one of three F1 driving champions" , "High point, but not a mountain" , "Canvasser of opinions" , "Mound (of mole, ants)" .)