The term pawn has two uses, both of which may be found in general and legal contexts. If you describe a person, group, institution, country or other thing as a pawn, then you are saying that it is being used by someone or something more powerful for its own purposes. For example, Hugo Chavez has long accused the Organisation of American States of being a US pawn.
In common usage, an item of pawn is an object left as security for money lent. The term can also be used as a verb, and someone might pawn their jewellery by leaving it in the possession of a pawnbroker as security for a loan. The pawnbroker will keep the jewellery until the person who left it is able to pay the loan, which must be within a certain time. If the person pawning the jewellery is unable to pay back the loan, the pawnbroker is allowed to sell the items without giving any notice.
The interest rates charged by pawnbrokers are high, and the amount of the loan is usually well below the value of the pawned property.
While pawnbrokers are relatively uncommon now, they do still exist in some jurisdictions – and are usually licensed by the state.