attain: [14] Unlike contain, maintain, obtain, and the rest of a very long list of English words ending in -tain, attain does not come from Latin tenēre ‘_hold’. Its source is Latin tangere ‘touch’ (as in English tangible and tangent). The addition of the prefix ad- ‘to’ produced attingere ‘reach’, which passed via Vulgar Latin *attangere and Old French ataindre into English. => tangent, tangible[attain etymology, attain origin, 英语词源]