Hilo hello (5)
I believe the answer is:
aloha
'hilo hello' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for aloha that I've seen before include "A halo seen in Polynesian greeting" , "greeting in Oahu" , "Hi! in Honolulu" , "Welcome to Honolulu!" , "16 across in Hawaii" .)