adj. (American).Downright; resolute; honest. [Western: the simile, common to most languages, is of a man standing, his back to the wall, resolute to accomplish his purpose.]
1858. Harpers Magazine, XVII. Sept., 563/1. His Herculean frame, and bold, FLAT-FOOTED way of saying things, had impressed his neighbors, and he held the rod in terrorem over them.
1871. Philadelphia Bulletin, 23 March. The row at St. Clements Church. Now the Committee of the vestry put their FOOT FLATLY down on auricular confession and priestly absolution.
1887. R. A. PROCTOR, Knowledge, 1 June. When, in America, General Grant said he had PUT HIS FOOT DOWN and meant to advance in that line if it took him all the summer, he conveyed the American meaning of the expression FLAT-FOOTED.