One business coming to a holiday island (5)
I believe the answer is:
ibiza
'holiday island' is the definition.
(I've seen this before)
'one business coming to a' is the wordplay.
'one' becomes 'i' (Roman numeral).
'business' becomes 'biz' (informal term for business).
'coming to' says to put letters next to each other.
'i'+'biz'+'a'='IBIZA'
(Other definitions for ibiza that I've seen before include "One of the Balearic Islands" , "holiday destination" , "Island in the Balearics" , "Mediterranean location" , "One of matching pair" .)