carpetbagger (n.)youdaoicibaDictYouDict[carpetbagger 词源字典]
also carpet-bagger, 1868, American English, scornful appellation for Northerners who went South after the fall of the CSA seeking private gain or political advancement. The name is based on the image of men arriving with all their worldly goods in a big carpetbag. Sense later extended to any opportunist from out of the area. [carpetbagger etymology, carpetbagger origin, 英语词源]
copperhead (n.)youdaoicibaDictYouDict
Trigonocephalus contortrix, 1775, American English, so called for color markings between its eyes; see copper + head (n.). Poisonous "sneak snakes" (because they bite without warning), the name is said to have been first used in reference to Northerners suspected of Southern sympathies in Greeley's New York "Tribune," July 20, 1861. Charles H. Coleman, "The Use of the Term 'Copperhead' During the Civil War" ["Mississippi Valley Historical Review" 25 (1938), p.263] traces it to an anonymous letter against Ohio anti-war Democrats in the Cincinnati "Commercial" newspaper in the summer of 1861. It seems not to have been in widespread use until summer 1862.
damn (v.)youdaoicibaDictYouDict
late 13c., "to condemn," from Old French damner "damn, condemn; convict, blame; injure," derivative of Latin damnare "to adjudge guilty; to doom; to condemn, blame, reject," from noun damnum "damage, hurt, harm; loss, injury; a fine, penalty," possibly from an ancient religious term from PIE *dap- "to apportion in exchange" [see Watkins]. The Latin word evolved a legal meaning of "pronounce judgment upon." Theological sense is first recorded early 14c.; the optative expletive use likely is as old.

Damn and its derivatives generally were avoided in print from 18c. to c. 1930s (the famous line in the film version of "Gone with the Wind" was a breakthrough and required much effort by the studio). The noun is recorded from 1610s; to be not worth a damn is from 1817. The adjective is 1775, short for damned; Damn Yankee, characteristic Southern U.S. term for "Northerner," is attested from 1812. Related: Damning.
doughface (n.)youdaoicibaDictYouDict
contemptuous nickname in U.S. politics for Northern Democrats who worked in the interest of the South before the Civil War; it was taken to mean "man who allows himself to be moulded." The source is an 1820 speech by John Randolph of Roanoke, in the wake of the Missouri Compromise.
Randolph, mocking the northerners intimidated by the South, referred to a children's game in which the players daubed their faces with dough and then looked in a mirror and scared themselves. [Daniel Walker Howe, "What Hath God Wrought," 2007]
Mask of dough is recorded from 1809, and the same image Randolph used is attested in another context by 1833. In contemporary use the expression was explained as referring to "the pale doughy faces of his frightened opponents" [Craigie] or "to liken them in timidity to female deer," which is frightened at her own shadow.
northern (adj.)youdaoicibaDictYouDict
Old English norþerna, norðerne "northern, Northumbrian, Scandinavian," cognate with Old High German nordroni, Old Norse norroenn (see north). With -erne, suffix denoting direction. Related: Northernmost. Northerner in U.S. geo-political sense is attested from 1831. Northern lights "aurora borealis" first recorded by that name 1721 (earlier north-light, 1706).
Samoyed (n.)youdaoicibaDictYouDict
Siberian Mongolian people, 1580s, from Russian samoyed (11c.), traditionally literally "self-eaters," i.e. "cannibals" (the first element cognate with same, the second with eat), but this might be Russian folk etymology of a native name:
The common Russian etymology of the name Samoyed, meaning "self-eater," deepened the Russians' already exotic image of far-northerners. The most probable linguistic origin of Samoyed, however, is from the Saami -- saam-edne, "land of the people" [Andrei V. Golovnev and Gail Osherenko, "Siberian Survival: The Nenets and Their Story," Cornell University, 1999]
Which would make the name a variant of Suomi "Finn." The native name is Nenets. As the name of a type of dog (once used as a working dog in the Arctic) it is attested from 1889.