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quar·an·tine (kwôrən-tēn, kwŏr-)
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n.
1.
a. A condition, period of time, or place in which a person, animal, plant, vehicle, or amount of material suspected of carrying an infectious agent is kept in confinement or isolated in an effort to prevent disease from spreading.
b. An action resulting in such a condition: the government's quarantine of the animals.
2.
a. An action to isolate another nation, such as a blockade of its ports or a severance of diplomatic or trade relations.
b. The condition of being isolated by such an action.
3. Computers The isolation of data or data transmissions in order to keep viruses, worms, or other malware from infecting a computer or computer network.
tr.v. quar·an·tined, quar·an·tin·ing, quar·an·tines
To isolate in quarantine.

[Italian quarantena, from Venetian dialectal Italian, quarantine of a ship (so called because the length of the quarantine was typically forty days), from Old Italian quarantina, period of forty days (such as one designated for fasting or penance), from quaranta, forty, from Latin quadrāgintā; see kwetwer- in the Appendix of Indo-European roots.]

quaran·tina·ble adj.

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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