Crossword Genius

Nasty bit of GBH (8)

Ross

I believe the answer is:

grievous

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'nasty' is the definition.
(thesaurus)

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(Other definitions for grievous that I've seen before include "Legal assault charge" , "This sort of bodily harms is serious" , "Deplorable" , "The "G" of GBH" , "Calamitous" .)

I've seen this clue in the Evening Standard.
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