Hamper; restrain (7)
I believe the answer is:
trammel
I believe this clue is a double definition.
'hamper' is the first definition.
(both can mean to restrict)
'restrain' is the second definition.
(I know that restrain is a more specific form of the action the trammel)
(Other definitions for trammel that I've seen before include "Constrain, impede" , "Limit, hamper" , "Hobble" , "bar" , "Three-layered fishing net - melt ram (anag)" .)