Definitions by EX_

osu! 

That circle clicking rhythm game that also an aiming game. Based on Osu! Tatakae! Ouendan. Probably the most popular rhythm game along with Guitar Hero and DDR. Spelled with a lowercase o and an exclamation mark at the end.

A: "What do you just play?"

B: "This game I just know. It's called Osu."
A: "IT'S SPELLED osu! U IDIOT TCVBVJGY..."
B: "Haha circle goes brrrrrrrrrrrr..."

osu! by EX_ February 25, 2021