The Brief:
A rage quit occurs when someone gets excessively angry and upset, usually while playing video games.

DEEP DIVE
“Rage quit” can be used as a noun or a verb. It refers to when someone, often suddenly, quits a video game because they are upset. Rage quitters may also yell, curse, throw things, or otherwise outwardly express their rage in reaction to losing in a video game or feeling that they have been cheated in some way.
The phrase can also be stylized rage-quit or ragequit. Sometimes it’s referred to as “Alt-F4” or “QQ,” which are keyboard commands for quitting applications.
Rage quitting is a common practice among gamers who sometimes get highly invested in what they are playing. The term is commonly used online on gaming-centric platforms like Discord and Twitch.