acrossyoudaoicibaDictYouDict[across 词源字典]
across: [13] English originally borrowed across, or the idea for it, from Old French. French had the phrase à croix or en croix, literally ‘at or in cross’, that is, ‘in the form of a cross’ or ‘transversely’. This was borrowed into Middle English as a creoix or o(n) croice, and it was not until the 15th century that versions based on the native English form of the word cross began to appear: in cross, on cross, and the eventual winner, across.
=> cross[across etymology, across origin, 英语词源]
across (adv.)youdaoicibaDictYouDict
early 14c., acros, earlier a-croiz (c. 1300), from Anglo-French an cros "in a crossed position," literally "on cross" (see cross (n.)). Prepositional meaning "from one side to another" is first recorded 1590s; meaning "on the other side (as a result of crossing)" is from 1750. Phrase across the board originally is from horse-racing, in reference to a bet of the same amount of money on a horse to win, place, or show.