Patchy bit of dinner, say (9)
I believe the answer is:
piecemeal
'patchy' is the definition.
'bit of dinner say' is the wordplay.
'bit of' becomes 'piece' (I've seen this before).
'dinner say' becomes 'meal' (dinner is a kind of meal).
'piece'+'meal'='PIECEMEAL'
(Other definitions for piecemeal that I've seen before include "a little at a time" , "Unsystematically" , "A bit at a time" , "by degrees" , "step by step" .)