Green’s Dictionary of Slang

1. a biting, stinging insect.

1866		C.H. Smith Bill Arp 54: Then suddenly pokes its head out like a catawampus and says, Booh!
1880		M. Collins Thoughts in My Garden I 244: Look at their [spiders] value in destroying wasps and blue-bottles, midges, and all manner of catawampuses, as the ladies call them .

2. (US, also catawampous) a peculiar or remarkable thing or person.

1872		Schele De Vere Americanisms 590: Catawampous, or catawamptious, a word enlarged in the West from catamount. This animal had already furnished the hunter with the expressive phrase, ‘he dropped on him like a catamount on a coon’.
1915		H.E. Rollins ‘A West Texas Word List’ in DN IV:iii 225: catawampus (or wampus) cat, n. A virago. ‘She’s a regular catawampus cat’.
1936		R.F. Adams Cowboy Lingo 236: This old catawampus comes rackin’ to town.