The most common and most likely answer to this crossword clue is the 7 letter word TRIDENT
T
R
I
D
E
N
T
More clues leading to the result TRIDENT
- Move across to pack explosive in missile system
- Missile shelter Rhode Island Democrat enters
- Spear I'd used in river
- Fish in river is not pike
- Spear I had thrown into river
- Go up to stop explosive weapon
- Missile I had briefly seen in river
- This is offensively loud if its head goes off!
- Don't start raucous jabber!
- Weapon detective found upside-down in river
Buddy explains!

The straight part
We know that "weapon" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case weapon = trident.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 TRIDENT mean?
TRIDENT noun- A three-pronged spear somewhat resembling a pitchfork.
- A curve of third order of the form: