ragtag (n.)youdaoicibaDictYouDict[ragtag 词源字典]
also rag-tag, "ragged people collectively," 1820, from rag (n.) + tag (n.); originally in expression rag-tag and bobtail "the rabble" (tag-rag and bobtail is found in 1650s), with bobtail an old 17c. word for "cur." Tag and rag was "very common in 16-17th c." [OED][ragtag etymology, ragtag origin, 英语词源]