一命归西

归西 literally means 'return to the West' — a Buddhist reference to 西方极乐世界 (xīfāng jílè shìjiè, the Western Pure Land of Amitabha Buddha). Dying = going home to the Western Paradise. The phrase predates Buddhism's full sinicization but anchored to the Pure Land tradition.

Informal and slightly humorous or callous, like English 'kick the bucket' or 'meet one's maker'. Don't use it in sympathy or formal contexts — use 去世 (qùshì) or 逝世 (shìshì) instead. Lao She used it with comic flair in 《四世同堂》.