computer mouse

In computing, a mouse (plural mice or mouses) functions as a pointing device by detecting two-dimensional motion relative to its supporting surface. Physically, a mouse consists of a small case, held under one of the user's hands, with one or more buttons. It sometimes features other elements, such as "wheels", which allow the user to perform various system-dependent operations, or extra buttons or features can add more control or dimensional input. The mouse's motion typically translates into the motion of a pointer on a display.
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Noun
1. a hand-operated electronic device that controls the coordinates of a cursor on your computer screen as you move it around on a pad; on the bottom of the mouse is a ball that rolls on the surface of the pad; "a mouse takes much more room than a trackball"
(synonym) mouse
(hypernym) electronic device
(part-meronym) mouse button