Hindrance, obstruction (10)
I believe the answer is:
impediment
This clue is a double definition.
'hindrance' is the first definition.
(I know that hindrance can be written as impediment)
'obstruction' is the second definition.
(I know that obstruction can be written as impediment)
(Other definitions for impediment that I've seen before include "opposition" , "Let" , "Obstacle" , "Hindrance, obstruction" .)