mouse

American  

[mous, mouz] / maʊs, maʊz /

noun

plural

mice

1. any of numerous small Old World rodents of the family Muridae, especially of the genus Mus, introduced widely in other parts of the world.

2. any similar small animal of various rodent and marsupial families.

3. a quiet, timid person.

4. Computers. a palm-sized, button-operated pointing device that can be used to move, select, activate, and change items on a computer screen.

5. Informal. a swelling under the eye, caused by a blow or blows; black eye.

6. Slang. a girl or woman.

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verb (used with object)

moused, mousing

1. to hunt out, as a cat hunts out mice.

2. Nautical. to secure with a mousing.

verb (used without object)

moused, mousing

1. to hunt for or catch mice.

2. to prowl about, as if in search of something.

   The burglar moused about for valuables.

3. to seek or search stealthily or watchfully, as if for prey.

4. Computers. to use a mouse to move the cursor on a computer screen to any position.

mouse British  

noun

1. any of numerous small long-tailed rodents of the families Muridae and Cricetidae that are similar to but smaller than rats See also fieldmouse harvest mouse house mouse

2. any of various related rodents, such as the jumping mouse

3. a quiet, timid, or cowardly person

4. computing a hand-held device used to control the cursor movement and select computing functions without keying

5. slang a black eye

6. nautical another word for mousing

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verb

1. to stalk and catch (mice)

2. (intr) to go about stealthily

3. (tr) nautical to secure (a hook) with mousing

mouse Scientific  

/ mous /

1. A hand-held input device that is moved about on a flat surface to direct the cursor on a computer screen. It also has buttons for activating computer functions. The underside of a mechanical mouse contains a rubber-coated ball that rotates as the mouse is moved; optical sensors detect the motion and move the screen pointer correspondingly. An optical mouse is cordless and uses reflections from an LED to track the mouse's movement over a special reflective mat which is marked with a grid that acts as a frame of reference.

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mouse Cultural  

1. A common device that allows the user to reposition an arrow on their computer screen in order to activate desired applications. The term mouse comes from the appearance of the device, with the cord to the main computer being seen as a tail of sorts.

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mouse Idioms  

1. see play cat and mouse; poor as a churchmouse; quiet as a mouse. Also see under mice.

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Discover More

The user usually sends signals to the computer when the user depresses or “clicks” a switch. A number of slang terms, such as “click on X” or “click and drag” have arisen from the appearance of symbols on a screen when a mouse is used.

Other Word Forms

• mouselike adjective

Etymology

Origin of mouse

before 900; Middle English mous (plural mis ), Old English mūs (plural mȳs ); cognate with German Maus, Old Norse mūs, Latin mūs, Greek mŷs

Example Sentences

Before the iPhone, Apple shook up home computing with the 1984 Macintosh, whose icon-based interface and mouse made computing accessible beyond specialists -- and sparked a legendary rivalry between Jobs and Microsoft's Bill Gates.

From Barron's • Mar. 29, 2026

In the new study, scientists used experiments in both human and mouse cells to identify the enzyme BMP1, which cuts SLIT3 into these two fragments.

From Science Daily • Mar. 28, 2026

He clicked the mouse on a window displaying several lines of Smalltalk code, made a minor edit, and returned to the text.

From Los Angeles Times • Mar. 24, 2026

The granddaughter of a traumatized mouse may still carry a certain characteristic, but her fundamental mousiness isn’t a result of such highly specific ancestral experiences, which operate in the narrowest crevices of evolution.

From The Wall Street Journal • Mar. 20, 2026

Another mouse doll landed at my feet, this one yellow and blue.

From "Klawde: Evil Alien Warlord Cat" by Johnny Marciano and Emily Chenoweth