Green’s Dictionary of Slang

(orig. US) to provide one with sufficient money with which to eat, live etc.

1879		Chicago Trib. 15 May 9/6: Judge Pendery [...] has been grub-staking a party of miners who were digging a shaft [DA].
1884		C.F. Lummis letter 30 Oct. in Byrkit Letters from the Southwest (1989) 52: He ‘grubstaked’ a dead-broke miner, advancing him about $7 worth of provisions from his little grocery.
1890		A.C. Gunter Miss Nobody of Nowhere 100: He grub-staked us, and we used to work on the Tillie mine together.
1907		W.M. Raine Bucky O’Connor (1910) 233: Do you think I’m a cheap piker? No, sir. You’ve got to let me grub-stake you.
1916		H.L. Wilson Somewhere in Red Gap 135: Angus had some money saved up, and what should he do with bits of it now and then but grubstake old Snowstorm Hickey.
1922		Morn. Tulsa Dly World (OK) 7 May 29/6: He’s going to grubsteak [sic] me to a nosebaggery.
1923		E. Hemingway letter 23 Jan. in Baker Sel. Letters (1981) 77: We have 6 to 8 months grub money ahead.
1927		W. Edge Main Stem 170: If you don’t get a job, come back and I’ll grubstake you for a few days.
1937		J. Worby Other Half 49: What name do you travel by when you’re not grub-staking?
1957		D. Niland Call Me When the Cross Turns Over (1958) 18: Fiddley Dick was grubstaking Billy Lomas.
1966		‘Tom Pendleton’ Iron Orchard (1967) 83: What do you plan to do with that little bitty fortune that you’ve dug out of the big money-mountain? Grub-stake yourself for a great big business enterprise, I presume.
1975		K. Willey Ghosts of the Big Country 151: Their generosity in ‘grub-staking’ bushmen and prospectors who were down on their luck earned them an El Dorado of credit and affection.
2001		(con. late 19C) C. Jeffords Shady Ladies of the Old West 🌐 Most [landladies] were hardheaded realists [...] yet warm-hearted to a fault, ready to grubstake the miner who’d partied his money away.