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mouse (mous)
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n. pl. mice (mīs)
1.
a. Any of numerous small rodents of the families Muridae and Cricetidae, such as the house mouse, characteristically having a pointed snout, small rounded ears, and a long naked or almost hairless tail.
b. Any of various similar or related animals, such as the jumping mouse, the vole, or the jerboa.
2. A cowardly or timid person.
3. Informal A discolored swelling under the eye caused by a blow; a black eye.
4. pl. mice or mous·es (mousĭz) Computers A handheld, button-activated input device that when rolled along a flat surface directs an indicator to move correspondingly about a computer screen, allowing the operator to move the indicator freely, as to select operations or manipulate text or graphics.
intr.v. (mouz, mous) moused, mous·ing, mous·es
1. To hunt mice.
2. To search furtively for something; prowl.
Phrasal Verb:
mouse over
To hold a computer pointer over (a particular object or area of a screen) so as to cause a pop-up box to appear or other change to occur.

[Middle English mous, from Old English mūs; see mūs- in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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