Quick time event
Also said as QTE, Press X to not die
A button prompt pops up during a scene, and you have a moment to press it. The name comes from the "quick timer events" in Shenmue's manual, though Dragon's Lair played this way back in 1983.
It keeps hands on the controller through a scene that would otherwise be a cutscene. The catch is that the player is watching for the prompt and not at the scene, so they miss what you staged.
Say it
“No QTE for the boulder. If it stays, show the button a full second ahead, allow 900 ms to press, and let a miss cost health, not a reload.”
Where you’ve seen it
Resident Evil 4 builds a whole knife fight with Krauser out of prompts in a cutscene, and failing one kills you. It also put them into scenes you thought you could put the controller down for.
Not to be confused with rhythm game
A rhythm game teaches a pattern you can learn and get better at. A QTE usually asks you to react to something you could not have predicted.