Expendable (adjective)

1. Able to be used up or consumed.
2. Able to be sacrificed for a greater purpose or goal.

Origin:

From expend + -able.

Examples:

1. The rocket carried an expendable upper stage to boost the payload into orbit.
2. The company considered the older employees as expendable and replaced them with new hires.
3. The resources were considered expendable and were used up without any reservation.
4. The soldiers were expendable in the eyes of the commanding officer.
5. The equipment was considered expendable and was left behind after the mission.