A shotgun is a type of gun that fires multiple projectiles at once, often used for hunting.
When someone says "shotgun" in a car, they usually mean they get to sit in the front passenger seat on the side closest to the driver. This tradition comes from the idea that if you call out "shotgun," you're claiming the best spot in the car with a good view of what's happening outside. If no one calls it first and someone just gets into the front seat, they might say something like "you're shotgunning!" to remind them they didn't get there first.
How common is "shotgun"?
Word shotgun is considered uncommon in modern English. It has a balanced usage among all categories: speech, fiction, newspapers and academic texts.
Definitions
noun
(firearms) A gun which fires loads typically consisting of small metal balls, called shot, from a cartridge.
Example: The farmer's son brought home a Thanksgiving turkey from the wild that he killed with his shotgun.
(slang) 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. Can also be used in situations of claiming other resources such as bedrooms.
Example: I call shotgun!
(US, especially Southern US) A one-story dwelling with no hallways or corridors, with the rooms arranged in a straight line.
Example: Elvis Presley was born in a two-bedroom shotgun in Tupelo, Mississippi.
(American football) 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.
(attributive, as a modifier) Relating to shotguns, either in a present or past sense.
Example: shotgun cartridges
(attributive, as a modifier) Relating to the threat of force or dubious means.
Example: shotgun wedding
(attributive, as a modifier) Relating to the use of numerous, diverse or indiscriminate means to achieve a particular result.
