Rough route, it's said (6)
I believe the answer is:
coarse
'rough' is the definition.
('coarse' can be similar in meaning to 'rough')
'route it's said' is the wordplay.
'route' becomes 'course' (course is a kind of route).
'it's said' shows a homophone (sound like).
'course' sounds like 'COARSE'.
(Other definitions for coarse that I've seen before include "Rought or crude" , "Rough, harsh" , "gross" , "Rough or crude, lacking refinement" , "Large-grained or rough to the touch" .)