A state where another party maintains
possession of something, but does not have full ownership of it, and must gaurontee that it can be sold back to
the original owner for a fixed amount.
Usually when you offer something (jewelry, property, etc) up for collateral, it is in "hawk". Possessor can be a bank, a pawn shop, an impound lot, etc; but is usually limited to legal matters.
You can get the item "out of hawk" by paying the money back, or filling
the contract out.