Rubbish trifle has glutinous quality (12)
I believe the answer is:
fiddlesticks
'rubbish' is the definition.
(both can mean nonsense)
'trifle has glutinous quality' is the wordplay.
'trifle' becomes 'fiddle' (trifle can mean to fiddle with).
'has glutinous quality' becomes 'sticks' (something which sticks or is sticky is glutinous).
'fiddle'+'sticks'='FIDDLESTICKS'
(Other definitions for fiddlesticks that I've seen before include "Bilge" , "Rhubarb" , "Blast!" , "Bother!" , "tripe" .)