bettermost

Most all the bettermost folks in these parts are axed, and the doctor, the lawyer, and the minister is invited; it's no skim-milk story, I do assure-you, but upper crust, real jam.

1839, Thomas Chandler Haliburton, The Clockmaker, Or Sayings and Doings of Sam Slick of Slickville

The "universal fermentation," which Mr. Hume (Chap. xlv.) describes as about the beginning of the seventeenth century, occasioned by the revival of letters, then first became operative in the diffusion of knowledge among the people, at least among the bettermost classes, enlarged men's ideas, and by a necessary consequence led to discussions of political rights, and dissatisfaction with abuses of all kinds […]

1861, Henry Brougham Baron Brougham and Vaux, “Revolting Doctrines of the Stuart Princes”, in The British Constitution

Not from smaller men, mind you, nor yet from our equals ; but what's simple impidence an' sauce not to be borne from the common sort, be just greatness of mind in the bettermost.

1904, Eden Phillpotts, The American Prisoner: A Romance of the West Country, page 183