doubloon (n.)youdaoicibaDictYouDict[doubloon 词源字典]
1620s, from French doublon (16c.) and directly from Spanish doblon a gold coin, augmentative of doble "double" (coin so called because it was worth twice as much as the Spanish gold pistole), from Latin duplus "double" (see double (adj.)). Also see -oon.[doubloon etymology, doubloon origin, 英语词源]