Field day in the outskirts of Fermanagh? (6)

I believe the answer is:

fleadh

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'field day in the outskirts of fermanagh?' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'field day in the outskirts of fermanagh?' is the wordplay.
'field' becomes 'lea' (I've seen this before).
'day' becomes 'd'.
'in the' indicates putting letters inside.
'outskirts of' says to hollow out the word (remove centre letters).
'fermanagh' with its centre taken out is 'fh'.
'lea'+'d'='lead'
'lead' inserted inside 'fh' is 'FLEADH'.

Can you help me to learn more?

(Other definitions for fleadh that I've seen before include "Irish festival" , "festival in Cork?" .)

I've seen this clue in The Telegraph.

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