In the past it was known as an elecronic device used to move the cursor on a computer screen.
It is now only a device for making idiotic puns.
Person: "My computer mouse isn't working"
Person who thinks they are original: "Have you tried giving it cheese? HahhshshsH!H1h1111!"
A person giving a serious definition on Urban Dictionary
Did you see that idiot explaining quantum physics on Urban Dictionary? Wow.