al fresco (adv.)youdaoicibaDictYouDict[al fresco 词源字典]
1753, Italian, literally "in the fresh (air)." Italian al represents a contraction of words from Latin ad "to" (see ad-) + ille "that." Alfresco also meant "painted on plaster that was still fresh or moist" (1764; see fresco).[al fresco etymology, al fresco origin, 英语词源]