After short wicked act boy is red (7)

I believe the answer is:

crimson

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'is red' is the definition.
(synonyms)

'after short wicked act boy' is the wordplay.
'after short wicked act' becomes 'crim' (I can't justify this - if you can you should believe this answer much more).
'boy' becomes 'son' (male child).
'crim'+'son'='CRIMSON'

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(Other definitions for crimson that I've seen before include "Shade of red" , "Flushed" , "Become red-faced" , "Flush" , "Deep red colour" .)

I've seen this clue in The Times.

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