Green’s Dictionary of Slang

1. fierce, pitiless; thus adv. catawampously.

1843–4		Dickens Martin Chuzzlewit (1995) 343: There air some catawampous chawers in the small way too, as graze upon a human pretty strong.
1856		Household Words XIII. 148: It had fallen a victim to the jaws of deadly alligator, or catawampous panther or fiercely-riled rattlesnake.
1874		Pacific Commercial Advertiser (HI) 1 Aug. 4/3: The avalanche of republicanism will drfown them in the maelstrom of catawampus obfuscation.
1888		Atlantic Monthly Dec. 826/1: Who but ye had larnin’ enough ter sense how his mind air catawampus jes’ on that idee.
1900		Times (Richmond, VA) 8 Nov. 4/2: Candidate Woolley appears to have been ‘catawampously’ and tetotaciously ‘chawed up’.

2. excessive.

1849

Taunton Courier 17 Jan. 8/2: Catawampus prices here, that’s a fact; but everybody’s got more dust than he knows what to do with.

3. ill-tempered, crotchety; in a tantrum.

1843		R. Carlton New Purchase I 265: The tother one what got most sker’d, is a sort of catawampus (spiteful).
1918		A. Brazil Patriotic Schoolgirl 279: ‘I’ll go away till you've got over your tantrums. It's what used to be called katawampus when I was small, and they generally spanked me for it’.
1935		N. Algren Somebody in Boots 5: The towns folk called him ‘catawampus,’ meaning that they thought him violently cross-tempered.

4. out of order, wrong.

1860		Isle of Wight Obs. 14 Apr. 3/4: Our brother Jonathan thought they might as well take a drink; the idea was not catawampus, and as they had got a case of champagne [...] they proceeded to extermporise the same by discomboblificating the bottles of the case which enclosed them.
1884		C.E. Craddock Where The Battle Was Fought 405: I kin prove ter ye that ye air all cat-a-wampus on that p’int.
2005		Arizona Republican (Phoenix, AZ) 3 Jan. E5/1: Cattywampus: Something that doesn’t fit or is out of line, in Texas.

5. (also cattywampus) askew; thus catawampously, catawamptiously.

1879		Morrison Gaz. (TN) 27 Aug. 4/1: Striking a mud puddle he would rear back his ewe neck, get catawampus with the road, p[and] curl his tail to one side.
1898		People’s Voice (Wellington, KS) 18 Aug. 8/2: Waggoner [...] got tangled up in trying to cross all of those catawampus bridges.
1901		Iola Register (KS) 12 Apr. 8/5: Hats, tilted at all possible angles, up in front, down behind, catawampus on the left ear [etc.].
1908		L.W. Payne Jr ‘Word-List From East Alabama’ in DN III:iv 297: catawampus, adj. or adv. Out of shape, askew; cross-ways, obliquely. Also pronounced cattywampus.
1911		L. Pound ‘A Second Word-List From Nebraska’ in DN III:vii 542: catawampus, cattywampus, adj. Crosswise, diagonal, askew, awry. ‘The clothesline ran catawampus in the backyard.’.
1918		St Joseph Obs. (MO) 12 Oct. 8/7: Brack then crept up to the door, slipped his revolver aeround the jamb, ‘catawampus like,’ and fired.
1931		National Geographic Mag. Dec. LX 734: A new fence post, set out of line, is ‘catawampus’ or ‘wapper-jawed’ [DA].
1939		P.G. Brewster ‘Folk “Sayings” From Indiana’ in AS XIV:4 266: Objects ‘out of plumb’ (i.e. off-center) are ‘si-gogglin,’ ‘catawampus,’ or ‘settin’ whopperjawed’.
1966		G. & K. Swarthout Whichaway (1967) 45: Each blow sent a bolt of agony through his whole body and almost knocked him cattywampus.

6. (also cattywhompus, (US campus) eccentric.

1997–2002

Hope College ‘Dict. of New Terms’ 🌐 cattywhompus adj. [...] 2. When a person does something out of the norm. For example, if a person starts to yell at trees, you would say ‘Look at that person, yelling at trees! They’ve really gone cattywhompus!’.