any of numerous small Old World rodents of the family Muridae, especially of the genus Mus, introduced widely in other parts of the world.
any similar small animal of various rodent and marsupial families.
a quiet, timid person.
Computers. a palm-sized, button-operated pointing device that can be used to move, select, activate, and change items on a computer screen. Compare joystick (def 2), stylus (def 3).
Informal. a swelling under the eye, caused by a blow or blows; black eye.