Rough track, say (6)
I believe the answer is:
coarse
'rough' is the definition.
('coarse' can be similar in meaning to 'rough')
'track say' is the wordplay.
'track' becomes 'course' ('course' can be a synonym of 'track').
'say' shows a homophone (sound like).
'course' sounds like 'COARSE'.
(Other definitions for coarse that I've seen before include "Rough to the touch or lacking refinement" , "Large-grained or rough to the touch" , "Rough-hewn" , "Rough, uncouth" , "Boorish" .)