sequester

1 of 2

verb

se·​ques·​ter si-ˈkwe-stər 

sequestered; sequestering si-ˈkwe-st(ə-)riŋ 

transitive verb

1

a

: to set apart : segregate

sequester a jury

b

: seclude, withdraw

… widely spaced homes are forbiddingly grand and sequestered.

—Don Asher

2

a

: 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

sequester

2 of 2

noun

1

: the imposition of automatic government spending reductions in accordance with sequestration

2

obsolete : separation, isolation

Did you know?

Sequester is a word that has important legal and scientific uses, and a long history besides. In fact, it can be traced back to the Latin preposition secus, meaning, well, “beside” or “alongside.” Setting someone or something apart (figuratively “to the side”) from the rest is sequester’s raison d’être. We frequently hear it in the context of the courtroom, as juries are sometimes sequestered for the safety of their members or to prevent the influence of outside sources on a verdict. It is also possible, legally speaking, to sequester property—sequester can mean both “to seize” and “to deposit” property by a writ of sequestration. The scientific sense of sequester most often encountered these days has to do with the binding or absorption of carbon. Kelp forests, for example, sequester massive amounts of carbon dioxide during photosynthesis, keeping it “apart” from the atmosphere—by some estimates doing so twenty times as much as terrestrial forests. You might even say kelp’s got this sequestering thing locked up.

Synonyms of sequester

Verb

• isolate
• separate
• remove
• segregate
• cut off

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 Broncos head coach and general manager are set to spend most of the first four weeks of April sequestered in front of a big screen in Denver’s team room, clickers in hand, watching tape of draft prospects. —Parker Gabriel, Denver Post, 5 Apr. 2026

The family home has been sequestered and investigators are now searching the premises for traces of the powerful poison, according to Marco Graziano, vice police commissioner at Campobasso police. —Barbie Latza Nadeau, CNN Money, 3 Apr. 2026

By returning carbon-laden clippings to the turf, the carbon is quickly reabsorbed and sequestered, reducing the amount of carbon dioxide in the atmosphere. —Megan Hughes, Better Homes & Gardens, 1 Apr. 2026

The landmark decision comes after a nearly seven-week trial, and as jurors in a federal court in California have been sequestered in deliberations for more than a week about whether Meta and YouTube should be liable in a similar case. —Morgan Lee, Los Angeles Times, 25 Mar. 2026

Word History

Etymology

Verb

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

First Known Use

Verb

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

Noun

1604, in the meaning defined at sense 2

Rhymes for sequester

• ancestor
• arrester
• digester
• investor
• protester
• requester
• semester
• silvester
• trimester
• ester
• esther
• fester

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Kids Definition

sequester

verb

se·​ques·​ter

si-ˈkwes-tər

sequestered; sequestering

-t(ə-)riŋ

1

: to set apart : segregate

the jury was sequestered until a verdict was reached

2

: to take custody of (as personal property) until a demand is satisfied

Medical Definition

sequester

1 of 2 transitive verb

se·​ques·​ter si-ˈkwes-tər 

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

sequester

2 of 2 noun

: sequestrum

Legal Definition

sequester

1 of 2 transitive verb

se·​ques·​ter si-ˈkwes-tər 

sequestered; sequestering

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.

2

a

: to seize especially by a writ of sequestration

b

: to deposit (property) in sequestration

sequester

2 of 2 noun

: sequestration sense 3

Etymology

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