Wiktionary
n. 1 A plot device that interrupts continuity in works of fiction, by returning characters and situations to the ''status quo'' they held before certain changes were introduced. 2 (context computing English) A button that resets something.
WordNet
n. a push button that you press to activate the reset mechanism
Wikipedia
In electronics and technology, a reset button is a button that can reset a device. On video game consoles, the reset button restarts the game, losing the player's unsaved progress. On personal computers, the reset button clears the memory and reboots the machine forcibly. Reset buttons are found on circuit breakers to reset the circuit. This button can cause data corruption so this button often doesn't exist on many machines. Usually, in computers and other electronic devices, it is present as a small button, possibly recessed into the case or only accessible by a pin or similar thin object, to prevent it being pressed accidentally .
Usage examples of "reset button".
Inside there, inside the Well, among other routine things, is something I can't really explain but which is, for all intents and purposes, a reset button.
She dug out a paperclip and unbent it to reach the reset button, grimacing at the screaming face that displayed on the screen as the thing rebooted.
This wasn't some kind of a game, where he could push a reset button if he missed a trick.
He again pressed the reset button, and watched the two approaching one another.
Gorshkov quickly pushed the Reset button on his target acquisition radar and confirmed what his wingman had reported.
As soon as she could, she tried to reset the generators with the ELEC CAUTION RESET button--no go, it kept on tripping off.
Chang studied them with a frown of annoyance, then pressed the RESET button.