He mows lawn for rolling, getting one from Barry? (10)

I believe the answer is:

welshwoman

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'he mows lawn for rolling getting one from barry?' is the definition.
The definition suggests a singular noun which matches the answer.

'he mows lawn for rolling getting one from barry?' is the wordplay.
'he mows lawn' can be anagrammed to 'WELSHWOMAN'.
Though, I'm not clear how this is indicated.

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I've seen this clue in The Guardian.

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