Upset everyone in island (7)
I believe the answer is:
rockall
'island' is the definition.
(I've seen this before)
'upset everyone' is the wordplay.
'upset' becomes 'rock' (rock can mean to upset or shake).
'everyone' becomes 'all' (all people).
'rock'+'all'='ROCKALL'
'in' acts as a link.
(Other definitions for rockall that I've seen before include "Uninhabited islet 290 miles west of Scotland" , "tiny outpost" , "Atlantic outcrop, annexed by UK in 1955" , "small island" , "British Atlantic islet" .)