Pawn (noun)

1. A person or thing that is used or sacrificed in order to gain an advantage or to further a plan.
2. A chess piece that moves forward and captures diagonally, and is the least valuable piece.
3. A piece of property that is left with a pawnbroker as collateral for a loan, typically of small value.

Origin:

From the old french word pan, meaning a pledge or security, which comes from the latin word pannus (cloth or piece of clothing) and the verb pendere (to weigh or balance), meaning a piece of property used as security for a loan.

Examples:

1. He used his brother as a pawn in his political game.
2. The pawn was moved to the last row and it was promoted to a queen.
3. He pawned his watch in order to get some quick cash.
4. The pawnbroker gave him a loan in exchange for the pawned ring.
5. He felt like he was being used as a pawn in someone else's scheme.