ladybug (n.)youdaoicibaDictYouDict[ladybug 词源字典]
1690s, from lady + bug (n.). The "lady" is the Virgin Mary (compare German cognate Marienkäfer). In Britain, now usually ladybird beetle (1704), through aversion to the word bug, which there has overtones of sodomy.[ladybug etymology, ladybug origin, 英语词源]