Boisterous Irish returned, supporting a band (3-7)
I believe the answer is:
rip-roaring
'boisterous' is the definition.
(thesaurus)
'irish returned supporting a band' is the wordplay.
'irish' becomes 'IR' (abbreviation for Irish).
'returned' says the letters should be written in reverse.
'supporting' becomes 'pro' (being pro something is supporting it).
'band' becomes 'ring' (a ring is a band of metal).
'ir' reversed gives 'ri'.
'ri'+'pro'+'a'+'ring'='RIP-ROARING'
(Other definitions for rip-roaring that I've seen before include "Exciting, boisterous" , "Wild and noisy" .)