profundity (n.)youdaoicibaDictYouDict[profundity 词源字典]
early 15c., "bottom of the sea," from Old French profundite (Modern French profondité) and directly from Late Latin profunditatem (nominative profunditas) "depth, intensity, immensity," from profundus "deep, vast" (see profound). Meaning "depth of intellect" in English is from c. 1500.[profundity etymology, profundity origin, 英语词源]