Pacific island with nothing, then a hospital and university (4)
I believe the answer is:
oahu
'pacific island' is the definition.
(I've seen this in another clue)
'nothing then a hospital and university' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'then' says to put letters next to each other.
'hospital' becomes 'H' (abbreviation for hospital).
'and' is a charade indicator (letters next to each other).
'university' becomes 'U' (abbreviation for university).
'o'+'a'+'h'+'u'='OAHU'
'with' is the link.
(Other definitions for oahu that I've seen before include "Honolulu's island" , "Pacific island" , "Chief island of Hawaii" , "Hawaiian island" , "popular Pacific location" .)