Coiffure that’s surprising at Irish party (6)
I believe the answer is:
hairdo
'coiffure' is the definition.
(synonyms)
'that's surprising at irish party' is the wordplay.
'that's surprising' becomes 'ha' (exclamation said when learning surprising news).
'at' is a charade indicator (letters next to each other).
'irish' becomes 'IR' (abbreviation).
'party' becomes 'do' (do is a kind of party).
'ha'+'ir'+'do'='HAIRDO'
(Other definitions for hairdo that I've seen before include "The process of styling hirsute head" , "Style for one's crowning glory" , "Possibly a DA" , "Possibly cut" , "What one may have expected from 'Sweeney Todd'" .)