Something that is spent has been used so that it no longer has any power or effectiveness.用尽的;失效的
spent bullets/matches乏弹/用过的火柴
After several defeats in a row, people are starting to say that the team is a spent force.球队经历了一连串的失利之后,人们开始认为他们已雄风不再。
literary tired疲惫的
We arrived home spent after our long journey.长途旅行之后,我们回到家时已疲惫不堪。