lukewarmyoudaoicibaDictYouDict[lukewarm 词源字典]
lukewarm: [14] Lukewarm is a compound adjective based on the now obsolete Middle English luke ‘tepid’. It is not altogether clear where this came from, but it is generally assumed to be a derivative of the also now obsolete lew ‘(fairly) warm’, with perhaps a diminutive suffix. Lew goes back to an Old English hlēow ‘warm’, a variant of which became modern English lee ‘shelter’. It is related to Latin calor ‘heat’ (source of English calorie), calidus ‘hot’ (source of English caudle, cauldron, and chowder), and calēre ‘be hot’ (source of English nonchalant).
=> calorie, cauldron, chowder, lee, nonchalant[lukewarm etymology, lukewarm origin, 英语词源]
lukewarm (adj.)youdaoicibaDictYouDict
late 14c., from luke + warm (adj.). Figurative sense of "lacking in zeal" (of persons or their actions) is from 1520s. Related: Lukewarmly; lukewarmness.