Good bread in fact stale (8)
I believe the answer is:
stagnant
'stale' is the definition.
(I've seen this before)
'good bread in fact' is the wordplay.
'good' becomes 'g' (abbreviation).
'bread' becomes 'nan' (variant spelling of naan).
'in' indicates putting letters inside.
'fact' becomes 'stat' (statistic).
'g'+'nan'='gnan'
'gnan' inserted inside 'stat' is 'STAGNANT'.
(Other definitions for stagnant that I've seen before include "Stale like still water" , "Foul from inertia" , "Without vitality" , "Showing little activity" , "making no progress" .)