Crossword Genius

Small boy in audition goes over lines randomly (12)

Ross

I believe the answer is:

crisscrosses

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'small boy in audition' is the definition.
I can't judge whether this definition defines the answer.

'goes over lines randomly' is the wordplay.
'goes over' becomes 'crosses' (I've seen this before).
'lines' indicates putting letters inside (line could historically mean to cover something).
'randomly' becomes 'isscr' (I can't explain this - if you can you should give a lot more credence to this answer).
'crosses' enclosing 'isscr' is 'CRISSCROSSES'.

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I've seen this clue in The Independent.
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