A "reminder" is a noun that refers to something that helps you remember a particular fact, event, or task. It serves as a prompt or cue that brings something to your attention so that you don’t forget it. For example, a reminder might be a note left on your desk, an alarm set on your phone, or an email notification about an upcoming deadline.
The word "reminder" originates from the combination of "remind" (which itself comes from the Latin word “remindere,” meaning “to bring to mind”) and the suffix “-er,” which denotes an agent or something that performs a function.