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i·so·late (īsə-lāt)
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tr.v. i·so·lat·ed, i·so·lat·ing, i·so·lates
1.
a. To cause to be alone or apart, as in being inaccessible or unable to move about: The police isolated the area until more help could arrive.
b. To place in quarantine.
c. To cause to become socially or politically unengaged or ostracized: an immigrant who was isolated by his poor language skills.
d. To render free of external influence; insulate: a system of government that isolated its citizens from foreign ideas.
2. To identify or distinguish as a separate entity or group: The study tried to isolate the effects of changing schools on student performance.
3.
a. Chemistry To separate (a substance) in pure form from a combined mixture.
b. Microbiology To separate (a pure strain of a microorganism or virus) from a mixed culture.
4. Psychology To separate (experiences or memories) from the emotions relating to them.
5. Electricity
a. To set apart (a component, circuit, or system) from a source of electricity.
b. To insulate or shield.
adj. (-lĭt, -lāt)
Separated from others: an isolate population.
n. (-lĭt, -lāt)
1. A person, thing, or group that has been isolated, as by geographic, ecologic, or social barriers.
2. Microbiology A population of microorganisms or viruses that has been isolated.
3. Linguistics A language isolate.

[Back-formation from ISOLATED.]

iso·lator n.

Synonyms: isolate, insulate, seclude, segregate, sequester
These verbs mean to separate from others: a mountain that isolated the village from larger towns; insulated herself from the chaos surrounding her; a celebrity who was secluded from public scrutiny; segregated the infectious patients in a special ward; sequestering a jury during its deliberations.

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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