[ noun mous; verb mouz ]
See synonyms for: mousemicemousedmouses on

noun,plural mice [mahys]. /maɪs/.
  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.

  1. a quiet, timid person.

  2. 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).

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

  4. Slang. a girl or woman.

verb (used with object),moused, mous·ing.
  1. to hunt out, as a cat hunts out mice.

  2. Nautical. to secure with a mousing.

verb (used without object),moused, mous·ing.
  1. to hunt for or catch mice.

  2. to prowl about, as if in search of something: The burglar moused about for valuables.

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

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

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

Other words from mouse

  • mouselike, adjective

Words that may be confused with mouse

Words Nearby mouse Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use mouse in a sentence

British Dictionary definitions for mouse


noun(maʊs) plural mice (maɪs)
  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 Related adjective: murine

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

  1. a quiet, timid, or cowardly person

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

  3. slang a black eye

  4. nautical another word for mousing

  1. to stalk and catch (mice)

  2. (intr) to go about stealthily

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

Origin of mouse

Old English mūs; compare Old Saxon mūs, German Maus, Old Norse mūs, Latin mūs, Greek mūs

Derived forms of mouse

  • mouselike, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for mouse


[ mous ]

Plural mice (mīs) or mouses
  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.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for mouse


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.

Notes for mouse

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.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Other Idioms and Phrases with mouse


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

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.