The most common and most likely answer to this crossword clue is the 9 letter word ARMISTICE
I've seen this crossword clue in The Times
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More clues leading to the result ARMISTICE
- It's a crime breaking a truce
- Peace created by fog and frost by a river
- Agreement to stop battling regularly hairy and dangerous driving conditions
- Prepare first off, an end to hostilities
- Give weapons to cities involved in ceasefire
- Delayed start for hostilities — bad weather combination brings ceasefire
- This stops fire using spray I found in unwrapped package
- Ceasefire due to a fog covering river, and the effect of freezing
- End of hostilities from division cities sorted out
- Peace for the time being — it’s a crime, if one breaks it
Buddy explains!

The straight part
We know that "an end to hostilities" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case an end to hostilities = armistice.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 ARMISTICE mean?
ARMISTICE proper noun- The armistice agreement signed between the Allies and Germany on 11 November 1918 to end World War I; (by extension) the end of World War I.
- A (short) cessation of combat; a ceasefire, a truce.
- A formal agreement, especially between nations, to end combat.