The most common and most likely answer to this crossword clue is the 9 letter word HONEYMOON
I've seen this crossword clue in The Times
H
O
N
E
Y
M
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N
More clues leading to the result HONEYMOON
Buddy explains!

The straight part
We know that "holiday" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case holiday = honeymoon.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does HONEYMOON mean?
HONEYMOON noun- The period of time immediately following a marriage.
- A trip taken by a newly married couple during this period.
- A period of goodwill at the beginning of a new term or relationship (e.g. towards a newly elected politician or in respect of a new business arrangement).
- To have a honeymoon (a trip taken by a couple after wedding).