Face a Celt screwed up, in a manner of speaking (9)

I believe the answer is:

dialectal

'in a manner of speaking' is the definition.
(relating to a dialect)

'face a celt screwed up' is the wordplay.
'face' becomes 'dial' (face of a clock).
'screwed up' indicates an anagram.
'a'+'celt'='acelt'
'acelt' with letters rearranged gives 'ectal'.
'dial'+'ectal'='DIALECTAL'

I've seen this clue in The Guardian.

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