The most common and most likely answer to this crossword clue is the 7 letter word SHOTGUN
I've seen this crossword clue in The Times
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More clues leading to the result SHOTGUN
- Firearm that’s initially carried by Japanese VIP
- Japanese governor carrying orient's latest weapon
- Warlord keeps head from thermonuclear weapon
- Got pissed to avoid going round for firearm
- Avoid holding hostage, regularly involving duress
- Old Japanese commander holding end of blunt weapon
- Well directed, it may finish off the game
- Warlord with grip on front of trigger in weapon
- Military governor, crossing sort of square, produces weapon
- Review on thug’s weapon
Buddy explains!

The straight part
We know that "Firearm" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case firearm = shotgun.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 SHOTGUN mean?
SHOTGUN noun- A gun which fires loads typically consisting of small metal balls, called shot, from a cartridge.
- The front passenger seat in a vehicle, next to the driver; so called because the position of the shotgun-armed guard on a horse-drawn stage-coach, wagon train, or gold transport was next to the driver on a forward-mounted bench seat.
- A one-story dwelling with no hallways or corridors, with the rooms arranged in a straight line.
- An offensive formation in which the quarterback receives the snap at a distance behind the center, often with a running back set to one or both sides of him.
- (as a modifier) Relating to shotguns, either in a present or past sense: e.g. shotgun cartridges, shotgun seat.
- (as a modifier) Relating to the threat of force or dubious means: e.g. shotgun wedding, shotgun diplomacy.
- (as a modifier) Relating to the use of numerous, diverse or indiscriminate means to achieve a particular result: e.g. shotgun marketing, a shotgun approach.
- (smoking) To inhale from a pipe or other smoking device, followed shortly by an exhalation into someone else’s mouth.
- To verbally lay claim to (something)
- To hit the ball directly back at the pitcher.
- To rapidly drink a beverage from a can by making a hole in the bottom of the can, placing the hole above one's mouth, and opening the top.
- To send out many (requests, answers to a question, etc), especially in the hope that one obtains a positive result (i.e. reveals useful information, is correct, etc), in the manner of a shotgun firing many balls of shot such that one may hit a target.
- To employ the technique of shotgun debugging.