quotidian (adj.)youdaoicibaDictYouDict[quotidian 词源字典]
mid-14c., "everyday, daily," from Old French cotidian (Modern French quotidien), from Latin quotidianus "daily," from Latin quotus "how many? which in order or number?" (see quote (v.)) + dies "day" (see diurnal). Meaning "ordinary, commonplace, trivial" is from mid-15c.[quotidian etymology, quotidian origin, 英语词源]