British supporter reduced criminal disturbance (8)
I believe the answer is:
ballyhoo
'criminal disturbance' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.
'british supporter reduced' is the wordplay.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'supporter' becomes 'ally' (ally can mean a supporter or friend).
'reduced' becomes 'hoo' (I can't explain this - if you can you should give a lot more credence to this answer).
'b'+'ally'+'hoo'='BALLYHOO'
Can you help me to learn more?
(Other definitions for ballyhoo that I've seen before include "Blatant advertising - a holy lob (anag)" , "Hubbub" , "Big to-do or advertising campaign" , "Noisy or sensational publicity, hype" , "Much fuss" .)