temporary inbox

https://mag-wiki.win/index.php/Understanding_the_Temporary_Email_Time_Limit:_What_You_Need_to_Know

A temporary inbox is like a disposable email address you can use when signing up for a service or offer that you don't completely trust. It keeps your primary email free from spam and unwanted newsletters. You get an address that works for a short while, usually an hour or so, and then it self-destructs. It's handy for one-time verifications or trials where you know you won't need follow-ups. Basically, it's a way to protect your real inbox from clutter and potential junk.