Garnishee

v. legally confiscate property (or money, etc.) for the purpose of repaying a debt

n. one whose assets have been garnished (Law)

A garnishment is a means of collecting a monetary judgment against a defendant by ordering a third party (the garnishee) to pay money, otherwise owed to the defendant, directly to the plaintiff.
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Verb
1. take a debtor's wages on legal orders, such as for child support; "His employer garnished his wages in order to pay his debt"
(synonym) garnish
(hypernym) impound, attach, sequester, confiscate, seize

(v. t.)
To make (a person) a garnishee; to warn by garnishment; to garnish.
  

(v. t.)
To attach (the fund or property sought to be secured by garnishment); to trustee.
  

(n.)
One who is garnished; a person upon whom garnishment has been served in a suit by a creditor against a debtor, such person holding property belonging to the debtor, or owing him money.
  

A summons issued by a plaintiff, against a third party, for seizure of money or other assets in their keeping, but belonging to the defendant