Green’s Dictionary of Slang

(US) used as a usu. negative intensifier, a var. on damned adj.; thus tarnally adv.

c.1776		E. Bangs ‘The Yankee’s Return From Camp’ in Silber Songs of Independence (1973) 78: I saw another snarl of men, / A-digging graves they told me, / So tarnal long, so tarnal deep.
1787		R. Tyler Contrast II ii: The snarl-headed curs fell a-kicking and cursing of me at such a tarnal rate, that I was glad to take to my heels.
1809		Horry & Weems Life of General F. Marion (1816) 124: They have got a tarnal nation sight of pistols!
1825		J. Neal Brother Jonathan I 158: I know your tarnal rigs, inside and out.
1833		C.A. Davis Letters of Major J. Downing (1835) 25: I have seen in your paper a ‘Crowner’s Inquest’ saying I was drowned [...] This is a tarnal lie.
1836		T. Haliburton Clockmaker I 61: A fifth is so etarnal cunning, all Cumberland couldn’t catch him.
1840		T. Haliburton Clockmaker III 200: It sarves you right, says I, for bein’ such a ’tarnal hypocrite.
1843–44		Dickens Martin Chuzzlewit (1995) 259: ‘A first-rate spanker, cap’en, was it? Yes?’ ‘A most e-tarnal spanker,’ said the skipper.
1848		Bell’s Life in Sydney 18 Nov. 3/3: I accordingly, your worship, puts the ’tamal smash on his winder in a moment of wexsation.
1850		W.K. Northall Life and Recollections of Yankee Hill 18: One feller said ‘Jest coming down?’ No, you tarnal fool, I’m jest comin’ up.
1860		C.J. Lever One of Them II 290: ‘’Tarnal snakes if it ain’t!’ broke out Quackinboss.
1875		M. Thompson Hoosier Mosaics 178: ‘Nil de mortuis nisi bonum,’ said the editor, ‘is my motto, which may be freely translated: “If you can’t say something good of the dead, keep your tarnal mouth shut about them!”’.
1887		G. Devol Forty Years a Gambler 256: I don’t feel good in these tarnal stiff things, nohow.
1896		H. Blossom Checkers 206: Ye ’re too tarnal shif’less.
1905		Times Dispatch (Richmond, VA) 16 July 31/2: [cartoon caption] ‘I tell yew, John Brown, this here tarnal business has got to tew stop’.
1907		D. Stewart Shadows of the Night in Illus. Police News 20 July 12/3: ‘What the tarnal good would have been the use of the old man’s gold to him?’.
1914		G.A. England ‘Rural Locutions of Maine and Northern New Hampshire’ in DN IV:ii 76: [...] Him an’ her was lollygaggin’ the hull ‘tarnal time.’.
1922		Joyce Ulysses 405: Tarnally dog gone my shins if this beent the bestest plood and prandyballs, none!
1934		‘The Company Cook’ in Lomax & Lomax Amer. Ballads and Folk Songs 559: The one we had was a regular cad [...] A cross betwixt a mule and a ’tarnal fool.
1950		A.B. Guthrie Way West 308: And when we get through, we got them tarnal hills.
1993		S. King Dolores Claiborne 248: What in holy tarnal hell has that got to do with what happened to him?