to release a person, animal, or thing so that he, she, or it can move or act freely

He untethered the pony and threw a blanket on him. 他解开小马的绳子，给它盖上一条毯子。

When success came, he untethered himself from his longtime literary agent. 当成功来临时，他摆脱了多年的文学经纪人。