天大 tiāndà of the utmost importance Origin Definitions Defs Strokes Stroke Words Sentences Sents 2 sentences 他说他有个天大的秘密。 tā shuō tā yǒu ge tiāndà de mìmì. He said he has a huge secret. Source: OpenSubtitles有什么天大的秘密？ yǒu shénme tiāndà de mìmì? What's the big secret? Source: OpenSubtitles