What device erases memories in Men in Black (1997)?

The device that erases memories in Men in Black (1997) is called a neuralyzer.

In the film, the secret Men in Black organization monitors extraterrestrial activity on Earth and protects its secrecy. Agents use the handheld neuralyzer to wipe or alter the memories of witnesses who have seen aliens or other classified events. A bright flash accompanies the device’s operation, after which an agent supplies a replacement explanation.

The film was directed by Barry Sonnenfeld and stars Tommy Lee Jones as Agent K and Will Smith as Agent J. It is loosely based on the Men in Black comic-book series created by Lowell Cunningham and published by Aircel Comics.

The term is often remembered as “memory eraser,” but that is a description rather than the device’s canonical name. “Neuralyzer” is the distinctive in-universe term used by the franchise.