What does sequester mean?

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From our dictionary:

se•ques•ter

Pronunciation: (si-kwes'tur), [key]
v.t.
1. to remove or withdraw into solitude or retirement; seclude.
2. to remove or separate.
3. Law.to remove (property) temporarily from the possession of the owner; seize and hold, as the property and income of a debtor, until legal claims are satisfied.
4. Internat. Law.to requisition, hold, and control (enemy property).