se·​ques·​ter | \ si-ˈkwe-stər How to pronounce sequester (audio) \
sequestered; sequestering\ si-​ˈkwe-​st(ə-​)riŋ How to pronounce sequester (audio) \

Definition of sequester

 (Entry 1 of 2)

transitive verb

1a : to set apart : segregate sequester a jury
b : seclude, withdraw widely spaced homes are forbiddingly grand and sequestered— Don Asher
2a : to seize especially by a writ of sequestration
b : to place (property) in custody especially in sequestration
3 : to bind (a metal or metal ion) in the form of a soluble complex or chelate by adding a suitable reagent for the purpose of preventing precipitation in water solution by chemical agents that would normally bring it about, of solubilizing precipitates already formed, or of otherwise suppressing undesired chemical or biological activity sequester calcium and magnesium ions in the softening of hard water also : to bind or absorb (carbon dioxide) as part of a larger chemical process or compound … half of the starting material will be used up and half will be char. That can then be put back on the fields, where it will sequester carbon and help grow the next crop. — Emma Marris



Definition of sequester (Entry 2 of 2)

1 : the imposition of automatic government spending reductions in accordance with sequestration
2 obsolete : separation, isolation

Synonyms & Antonyms for sequester

Synonyms: Verb

Antonyms: Verb

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Sequester first appeared in English in the 14th century. The word derives from Latin sequestrare ("to hand over to a trustee") and ultimately from secus ("beside," "otherwise"), which is akin to Latin sequi ("to follow"). In this relationship, we can trace links to words such as sequel, sequence, consequence, and subsequent, all of which convey a meaning of one thing following another. These days, we most frequently hear sequester used in legal contexts, as juries are sometimes sequestered for the safety of their members or to prevent the influence of outside sources on a verdict. In a different sense, it is possible to sequester property in certain legal situations.

Examples of sequester in a Sentence

Verb The jury was sequestered until a verdict was reached. He was sequestered in his room.
Recent Examples on the Web: Verb The problem, however, is that segmentation remains difficult and time-consuming—even requiring physical, manual efforts to sequester different parts of the organization. Benny Lakunishok, Forbes, 25 July 2022 CF Industries’ major new investments are in plants that will rely on renewable energy sources rather than natural gas, or would capture the carbon emissions from using gas and sequester them underground. Laura Reiley, Washington Post, 14 July 2022 Card 1 of 4 New C.D.C. guidelines Hoping to prevent further disruptions to daily life, the C.D.C. reduced the period that certain infected Americans must sequester to five days from 10. Marc Santora, New York Times, 29 Dec. 2021 That’s the verdict served up by several preliminary studies and press releases out this week, describing how well antibodies, isolated from the blood of vaccinated people, recognize and sequester the new variant in a lab. Katherine J. Wu, The Atlantic, 8 Dec. 2021 And would seawater—which would already be used to sequester CO2 in Kelemen’s plan—be a candidate for such fracking? Scientific American, 18 Oct. 2021 Which is all to say: Betting on new peat to sequester the extra carbon that humanity is pumping into the atmosphere is a bad move, as there’s no guarantee the balance between recent growth and ongoing loss will tip in our favor. Matt Simon, Wired, 18 May 2022 Some also said efforts to sequester carbon in natural systems should go beyond tree-planting to focus on restoring soil and supporting farming techniques that capture carbon. Deborah Sullivan Brennan, San Diego Union-Tribune, 26 Mar. 2022 Besides that, the product has a 12-month shelf life and seaweed used to make Sway materials can sequester up to 20 times more carbon per acre than trees, all without requiring freshwater, land, pesticides or other inputs. Jeff Kart, Forbes, 3 Nov. 2021 Recent Examples on the Web: Noun As of 2022, SPLT’s carbon-credit sales have brought in approximately $1.2 million and sequester more than 15,000 metric tons of carbon dioxide per year—about as much as burning 16 million tons of coal emits. Julia Rosen, The Atlantic, 25 July 2022 In fact, researchers hope to one day sequester massive quantities of carbon by sinking kelp into the deep ocean. Lauren Oster, Smithsonian Magazine, 23 June 2022 In cities, living structures like the footbridge designed by Professor Ludwig can help sequester carbon, create a cooling effect, and provide a habitat to birds and other urban wildlife. Anne Pinto-rodrigues, The Christian Science Monitor, 8 June 2022 Ecobricks sequester plastic from the global waste stream. Tim Newcomb, Popular Mechanics, 20 May 2022 Tidal marshes such as those found along the lagoons on San Diego County’s coast sequester carbon in deep layers of soil. Deborah Sullivan Brennan, San Diego Union-Tribune, 2 May 2022 Lackner said to balance out the planet's carbon budget, the trees would need to move beyond the market and sequester CO2. Zayna Syed, The Arizona Republic, 22 Apr. 2022 In the former case, the terrestrial gear can, over tens of thousands of years, mesh with the geological gear to more or less permanently sequester carbon. Erik Kobayashi-solomon, Forbes, 14 Mar. 2022 The armed services are still trying to recover from sequester budget cuts, which started in 2013 and brutalized readiness. Kate Bachelder Odell, WSJ, 17 Feb. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sequester.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of sequester


14th century, in the meaning defined at sense 1a


1604, in the meaning defined at sense 2

History and Etymology for sequester


Middle English sequestren, from Anglo-French sequestrer, from Latin sequestrare to hand over to a trustee, from sequester third party to whom disputed property is entrusted, agent, from secus beside, otherwise; akin to Latin sequi to follow

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The first known use of sequester was in the 14th century

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sequential system



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Last Updated

4 Aug 2022

Cite this Entry

“Sequester.” Dictionary, Merriam-Webster, Accessed 10 Aug. 2022.

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More Definitions for sequester


transitive verb
se·​ques·​ter | \ si-ˈkwes-tər How to pronounce sequester (audio) \

Medical Definition of sequester

 (Entry 1 of 2)

: to hold (as a metallic ion) in solution especially for the purpose of suppressing undesired chemical or biological activity



Medical Definition of sequester (Entry 2 of 2)


transitive verb
se·​ques·​ter | \ si-ˈkwes-tər How to pronounce sequester (audio) \
sequestered; sequestering

Legal Definition of sequester

 (Entry 1 of 2)

1 : to place (as a jury or witness) in seclusion or isolation

Note: Juries are sequestered in order to preserve their impartiality. Witnesses are sequestered so that their testimony is not influenced by the testimony of prior witnesses.

2a : to seize especially by a writ of sequestration
b : to deposit (property) in sequestration



Legal Definition of sequester (Entry 2 of 2)

History and Etymology for sequester

Transitive verb

Anglo-French sequestrer, from Middle French, from Latin sequestrare to hand over to a trustee, from sequester third party to whom disputed property is entrusted, agent, from secus beside, otherwise

More from Merriam-Webster on sequester

Nglish: Translation of sequester for Spanish Speakers

Britannica English: Translation of sequester for Arabic Speakers


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