Not really a horn at all. This is the use of vocal power in the same manner as a horn in order that one might avoid using the real automotive horn on account of it sounding too "wussy."
"I don't use my real horn. It sounds too wussy so I just stick my head out the window and yell."
When a woman(or gay man) invites a man to their home under the pretext of a friendly hang out, but with their subtext being, "I'm gonna fuck that guy."
Sweetie, I went to hang out with Sarah and she jumped me.
That bitch tried to hornswaggle you?! I never trusted her.
The only non-percussion instrument in a classical orchestra that can be played with just one hand. It was invented to be like this because the horn player's other hand is usually otherwise occupied.
French Horns are great instruments, but you wouldn't want to meet a French Hornist.