Refuses to accept one is among hills (7)
I believe the answer is:
disowns
'refuses to accept' is the definition.
The answer and definition can be both to do with ownership as well as being verbs in their -s form.
Perhaps there's an association between them I don't understand?
'one is among hills' is the wordplay.
'among' means one lot of letters goes inside another (inserted letters are placed among others).
'hills' becomes 'downs' (I've seen this before).
'is' going inside 'downs' is 'DISOWNS'.
Can you help me to learn more?
(Other definitions for disowns that I've seen before include "Refuses to acknowledge" , "Has nothing to do" .)