Crossword Genius

Furious about gang leader's teasing (7)

Ross

I believe the answer is:

ragging

'teasing' is the definition.
('rag' can be a synonym of 'tease')

'furious about gang leader's' is the wordplay.
'furious' becomes 'raging' ('raging' can be a synonym of 'furious'**).
'about' is an insertion indicator.
'leader' suggests taking the first letters.
The first letter of 'gang' is 'g'.
'raging' placed around 'g' is 'RAGGING'.

(Another definition for ragging that I've seen is " Teasing, joshing".)

I've seen this clue in The Telegraph.
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