Roughly haul about somewhat, as usual (8)
I believe the answer is:
habitual
'usual' is the definition.
(I've seen this before)
'roughly haul about somewhat' is the wordplay.
'roughly' indicates anagramming the letters.
'about' is an insertion indicator.
'somewhat' becomes 'abit' (a bit).
'haul' with letters rearranged gives 'hual'.
'hual' going around 'abit' is 'HABITUAL'.
'as' is the link.
(Other definitions for habitual that I've seen before include "A halibut? (anag)" , "Done regularly and repeatedly" , "Commonly practised" , "Customary, regular" , "set" .)