mossback (n.)youdaoicibaDictYouDict[mossback 词源字典]
"conservative," 1874, especially of poor whites from Carolina, originally (1872) in reference to those who hid out to avoid service in the Confederate army (and would have stayed out till the moss grew on their backs); from moss + back (n.).[mossback etymology, mossback origin, 英语词源]