Disorderly Irish soldier (9)

I believe the answer is:

irregular

'disorderly' is the definition.
(thesaurus)

'irish soldier' is the wordplay.
'irish' becomes 'ir' (abbreviation).
'soldier' becomes 'regular' (member of the regular army).
'ir'+'regular'='IRREGULAR'

(Other definitions for irregular that I've seen before include "Unsymmetrical; soldier" , "Erratic" , "unusual for a > partisan?" , "Abnormal" , "Disorderly, uneven" .)

I've seen this clue in The Telegraph.

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