Abandon holiday (5)
I believe the answer is:
leave
I believe this clue is a double definition.
'abandon' is the first definition.
(to abandon something is to leave it behind)
'holiday' is the second definition.
(I know that holiday can be written as leave)
(Other definitions for leave that I've seen before include "Break" , "Renounce" , "Depart, go" , "Relinquish - holiday" , "Green light" .)