Crossword Genius

Unruly old boy upset superstore (12)

Ross

I believe the answer is:

obstreperous

'unruly' is the definition.
('obstreperous' can be a synonym of 'unruly')

'old boy upset superstore' is the wordplay.
'old boy' becomes 'ob'.
'upset' indicates anagramming the letters.
'superstore' anagrammed gives 'streperous'.
'ob'+'streperous'='OBSTREPEROUS'

(Other definitions for obstreperous that I've seen before include "Noisy, hard to control" , "Sober posture (anag) - unruly" , "Noisily defiant" , "Bolshie" , "Noisily aggressive" .)

I've seen this clue in The Times.
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