car horn, n.All

A Car horn is a mechanical scream

The Car horn is a device that should play only either C, E, or G, so every traffic jam would be a beautiful harmony

A Car horn is basically a "hey, quit looking at your phone" indicator.

The Car horn is the universal noise for both "hello" and "fuck you"

A Car horn is New York for "go fuck yourself."

A Car horn is a very small punching bag

A Car horn is a verbal middle finger

A Car horn is used for swearing in automobelese