Is thickset criminal more vulgar than anyone else? (10)

I believe the answer is:

kitschiest

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'more vulgar than anyone else?' is the definition.
I can't judge whether this defines the answer.

'is thickset criminal' is the wordplay.
'criminal' is an anagram indicator.
'is'+'thickset'='isthickset'
'isthickset' is an anagram of 'KITSCHIEST'.

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I've seen this clue in The Sunday Times and The Times.

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