Clever grown-up skipping third of Ulster, taking in Ireland (6)

I believe the answer is:

adroit

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'clever' is the definition.
(synonyms)

I can't explain the remainder of the clue.

(Other definitions for adroit that I've seen before include "Quick and deft" , "Quick or adept" , "Quick or skilful" , "Deft and proficient" , "Skilful or ingenious" .)

I've seen this clue in The Guardian.

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