1. to shut up in a pound or other enclosure, as a stray animal.
2. to confine within an enclosure or within limits: water impounded in a reservoir.
3. to seize and retain in custody of the law, as a document for evidence.
money, property, etc., that has been impounded: a sale of impounds by the police department.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.