mouse

American  

[mous, mouz] / maʊs, maʊz /

noun

• mice
  plural

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

Derived Forms

• mouselike
  adjective

Inflected Forms

Nouns

• mice
  plural

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

Explanation

A small rodent with a pointy face, rounded ears, and a long tail is called a mouse. A mouse may be kept as a pet, or it may be an uninvited guest in your home. A person who is timid and shy can also be called a mouse. In computer terms, a mouse is a corded or wireless device that moves your computer's cursor while you move the mouse. In most cases, the plural of mouse is "mice," but more than one computer mouse can also be called "mouses." Mouse can also be a verb in this context, like when you mouse over an icon to select a link.

Example Sentences

See Examples For:

mouse mice moused mousing

Clad in a blue suit and squinting at a computer screen in his office, Putin leaned forward and clicked his mouse.

From The Wall Street Journal ● Sep. 18, 2026

In a different Alzheimer's mouse model, a diet enriched with L-serine increased blood levels of both L-serine and D-serine and partially restored measures of new neuron production in the hippocampus.

From Science Daily ● Sep. 18, 2026

The team examined mouse neurons grown in the laboratory, neurons from adult mice and neurons from mouse embryos.

From Science Daily ● Sep. 17, 2026

In the new mouse study, the scientists followed proteins as they moved out of the brain, through these channels, and into the skull bone marrow.

From Science Daily ● Sep. 17, 2026

He smiled back and put the mouse in his vest pocket.

From "Rump: The (Fairly) True Story of Rumpelstilskin" by Liesl Shurtliff

Reducing Menin in younger mice increased hypothalamic inflammation and brought on several aging-related traits, including lower bone mass, thinner skin, cognitive decline, and a modestly shorter lifespan.

From Science Daily ● Sep. 18, 2026

Thirty days later, the treated mice had improvements in skin thickness and bone mass, along with better performance on tests of learning, cognition, and balance.

From Science Daily ● Sep. 18, 2026

The study also reported that restoring Menin extended lifespan in the treated mice.

From Science Daily ● Sep. 18, 2026

Related research has since documented pearled axons in human brain tissue, extending the observations beyond mice.

From Science Daily ● Sep. 17, 2026

The Los Baños internment camp is also overrun with mosquitoes, bedbugs, rats, mice, roaches, centipedes, flies, tarantulas, and snakes.

From "At Last She Stood" by Erin Entrada Kelly

I moused over the exclamation mark next to “Onboarding” and a helpful pop-up appeared.

From Slate ● Jan. 13, 2026

For one, the dock occasionally disappeared when I opened a full-screen Chrome tab in laptop mode, and it didn’t pop up when I moused around the bottom of the screen.

From The Verge ● Aug. 31, 2022

I have moused and clicked through a few, mostly ones I could watch without covering the screen whenever the children walked by.

From New York Times ● Apr. 16, 2020

Jamie videoed her dance routine and then they ran it in slow motion and moused it into shape, speeding up moves or slowing them down, repositioning legs, arms and head.

From Nature ● Mar. 17, 2015

People stood about looking on; some poked at the embers of the smoky fires, some moused and prowled about to see what scrap they might pick up.

From The Hidden Children by Robert W. (Robert William) Chambers

He was moved out of the department's central London building during the Covid pandemic and in 2020 he formally retired from his mousing duties.

From BBC ● Feb. 5, 2025

Typing and mousing for long periods is stressful for the finger and wrist muscles as well as the forearms.

From Los Angeles Times ● Jan. 28, 2025

When mousing in snow, the fox's long snout also allows it to reach its prey earlier, as mice are very sensitive to movements in their environment and can quickly escape.

From Science Daily ● Apr. 29, 2024

If the DeskPad feels like overkill, try Logitech’s $19.99 Desk Mat, a soft-cloth mat with a nice mousing feel in an assortment of soft colors.

From Seattle Times ● Dec. 28, 2023

It ain’t nowhere near’s sly nor quick as a cat; it ain’t no good at all at mousing nor catching holt of birds without a lot of help.

From "The Journey of Little Charlie" by Christopher Paul Curtis