Extensive clothing made by stunted gnome (4)
I believe the answer is:
maxi
'extensive clothing' is the definition.
'stunted gnome' is the wordplay.
'stunted' means to remove the last letter (the word is shorter than it usually is).
'gnome' becomes 'maxim' (both can mean a saying).
'maxim' with its last letter removed is 'MAXI'.
'made by' acts as a link.
(Other definitions for maxi that I've seen before include "Ankle-length skirt" , "full length garment" , "racing yacht" , "full-length garment" , "Full-length skirt" .)