The most common and most likely answer to this crossword clue is the 9 letter word CEASEFIRE
I've seen this crossword clue in The Times
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More clues leading to the result CEASEFIRE
- Drop weapons and relieve force to stop constant fury
- About to relax by heater in a state of peace
- Truce for review of Erica’s fee
- Stop fighting lawsuit involving English sack
- Unusually fierce sea battle ends with it
- Eire faces uneasy truce
- Cabinet axe housing English, as rest in conflict
- Charlie’s discharge interrupted by moderate truce
- Armistice — constant calm following fury
Buddy explains!

The straight part
We know that "Drop weapons" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case drop weapons = ceasefire.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 CEASEFIRE mean?
CEASEFIRE noun- In warfare, an agreed end to hostilities for a specific purpose. (Typically only temporary).