Mouse

A mouse is a small animal with a pointed nose, round ears, and a long tail, often found in fields or houses. The word also refers to the hand-held device used to control a computer cursor on the screen.

From Old English *mūs*, related to German *Maus* and Latin *mus*, from a very old Indo-European root. The computer sense was coined in the 1960s because the device was small and had a “tail” like the animal.