Limits of expansion in dull material (5)
I believe the answer is:
denim
'material' is the definition.
(type of fabric)
'limits of expansion in dull' is the wordplay.
'limits of' says to hollow out the word (remove centre letters).
'in' is an insertion indicator.
'dull' becomes 'dim' (synonyms).
'expansion' with its centre taken out is 'en'.
'en' going into 'dim' is 'DENIM'.
(Other definitions for denim that I've seen before include "Mined (anag)" , "Twilled cotton fabric" , "Hard-wearing cotton fabric" , "Hard-wearing clothing material, twilled cotton" , "maker of jeans" .)