Fine fabric produced by large detached territory (5)
I believe the answer is:
lisle
'fine fabric' is the definition.
(I've seen this before)
'by large detached territory' is the wordplay.
'by' is a charade indicator (letters next to each other).
'large' becomes 'l'.
'detached territory' becomes 'isle' (I've seen this before).
'l' next to 'isle' is 'LISLE'.
'produced' acts as a link.
(Other definitions for lisle that I've seen before include "Pedestrianised city" , "Fine smooth cotton thread for stockings" , "Cotton stocking thread" , "Strong cotton material" , "Strong cotton fabric" .)