人命关天 rénmìngguāntiān a matter of life and death Origin Definitions Defs Strokes Stroke Words Sentences Sents 人命 rénmìng human life human life; a person's life关 關 guān verb to concern To involve; to have a bearing on; to implicate天 tiān essential person or thing the person or thing one depends on for survival; the most important thing in one's life