Green’s Dictionary of Slang

1. describing the notes issued by a wildcat bank, thus of any money or finances, worthless, fraudulent.

1838		Jeffersonian 15 Sept. 244/1: We shall have [...] Lumbermen’s bills, and Wild-cat Bills, that nobody knows who the father or the maker is [DA].
1842		C.M. Kirkland Forest Life I 111: We took our pay in wild-cat money, that turned to waste paper before we got it off our hands.
1853		La Crosse Democrat 26 July 3/2: More than half his money was Wild Cat and counterfeit [DA].
1858		Sun (Baltimore) 8 July n.p.: Certain it is that we are overrun with a wild-cat currency [F&H].
1871		A. Daly Divorce 53: I invested in some wild-cat stock [DA].
1872		Schele De Vere Americanisms 297: Another term of similar character was the Wild-Cat Money of the last generation, which took its name from the notes of a bank in Michigan, bearing a Wild Cat or a panther on its face as a vignette.
1877		Stark Co. Democrat (Canton, OH) 15 July 1/2: They are opposed to all wild cat, red dog, rag baby money schemes of issuing paper dollars without limit.
1888		Century mag. (N.Y.) XXXVI 763/2: State treasury-notes were circulated in profusion, while ‘wild-cat’ bank-notes of all sorts, shapes, and sizes vied with the ‘shinplaster’ utterances [DA].
1896		J.F. Lillard Poker Stories 56: He [...] got a lot of wildcat money, wrapped it around with a couple of twenties, and put some fives in the middle.
1898		Binstead & Wells Pink ’Un and Pelican 231: Like a vulgar confidence trickster with a roll of wildcat money and one good ’un wrapped around the outside.
1904		Sun. Times (Perth) 20 Mar. 8/2: When the Commercial Bank went bung in the boom collapse [...] A. E. Clarke and Co. owed the bank £250.000—mostly in old-time silver boom wild-cat scrip.
1914		Ade ‘The New Fable of Susan and the Daughter’ in Ade’s Fables 216: With only three Gills of Stone Fence under his Wammus, he spread his Wild-Cat Currency on the Counter.

2. fraudulent, highly speculative.

1862		Sacramento Union (CA) 11 Jan. 6/7: Candidates are plentiful as ‘wild cat claims in the Flowery District’ .
1872		‘Mark Twain’ Roughing It 306: These were nearly all ‘wild cat’ mines and wholly worthless. [Ibid.] 307: By wild cat I mean, in general terms, any claim not located on the mother vein.
1880		G.T. Ingham Digging Gold 447: A Very Common Swindle is from what are called ‘Wild-Cat Mines’ [DA].
1890		Utah Valley Gazette 3 Jan. 2/2: A boom for this city is at hand — not a wild cat boom either, but a solid and rapid growth [DA].
1904		Seattle Repub. (WA) 19 Aug. 4/3: Dr Burdett’s colonization scheme [...] seemns to smack largely of a ‘wildcat scheme’. The coon getting the dough and the cat the cahoot.
1907		Sun. Times (Perth) 27 Oct. 4/8: Well-known wildcat promoter recently rushed into this office, brandishing a telegram [etc.].
1911		H.B. Wright Winning Barbara Worth 309: The S. & C. is not spending money to help out wild-cat projects promoted by eastern capital [DA].
1924		Collier’s 2 Feb. 12/1: Now don’t you go in for these wildcat oils [DA].
1938		M. Thompson High Trails of Glacier National Park 123: Altogether eleven wildcat oil companies were incorporated to operate between the railroad and the Canadian line [DA].
1984		W. Murray Tip on a Dead Crab 227: Egbert [...] declared that since he had stopped gambling, he could now invest in wildcat oil wells and penny mining stocks.

3. (orig. US) of a business practice, unsound, dubious; esp. in phr. wildcat bank.

1838		N.Y. Advertiser and Express 14 Feb. 1/2: These institutions have very properly received the soubriquet, of ‘wild cat banks’ [DA].
1853		Daily Morning Herald (St. Louis) n.p.: In 1837–8 Michigan was over-run with ‘wild-cat’ banks.
a.1859		Cincinnati Enquirer n.p.: Our banks are always willing to offer loans and facilities to speculators and wild-cat business men to operate with [DA].
1865		G.A. Sala My Diary in America I 240: He deserted his wife and family, drew cheques upon wild-cat banks.
1872		Galaxy (N.Y.) Apr. 496: The former are formed of three-number combinations, are drawn twice each day, and in the days of wildcat banks, whatever may be the fact now, paid their prizes in depreciated paper money.
1877		Galaxy (N.Y.) 632: When the Yankee mind stoops to criminal pursuits, it is likely to manifest itself in the way of bank forgeries, embezzlements [...] or wild-cat banking institutions [F&H].
1880		Highland Wkly News (Hillsboro, OH) 23 Sept. 3/5: The days of ‘wild-cat’ banks, when the laborer went to bed with fifty dollars [...] not having any assurance whether it would buy his breakfast in the morning.
1882		G.A. Sala America Revisited I 284: What are those scraps? Protested cheques, torn-up notes on ‘wild-cat’ banks.
1894		G.A. Sala Things I Have Seen II 91: A promoter of bog companies and ‘wild cat’ proprietory clubs.
1908		‘O. Henry’ ‘Shearing the Wolf’ in Gentle Grafter (1915) 110: It’s you supposedly respectable citizens [...] that support the lotteries and wild-cat mines and stock exchanges and wire tappers of this country.
1916		P. Kyne Cappy Ricks 244: He didn’t invest the thousand in a wild-cat mine or a dry oil well?
1923		N. Anderson Hobo 253: The ‘wild cat’ local mission, more or less ephemeral in nature, springs up during some crisis.
1925		Dos Passos Manhattan Transfer 307: If this ever gets wound up will you promise me not to go in for any more wildcat schemes?
1928		D. Lawley Hustling Hobo 248: Bret contined to ‘shoot his head off’ about the ‘wild-cat’ scheme, for he was out to spread the truth.
1930		‘Dean Stiff’ Milk and Honey Route 57: The wild-cat missions come and go with the misery seasons.
1940		Black Mask Mar. XXII 13: A wildcat bus company had its ‘depot’ in the tiny lobby.
1958		‘Ed Lacy’ Room to Swing 16: Mostly wild-cat jobs.