FOIL Meaning of FOIL in English I . v. a. Defeat, frustrate, balk, baffle, thwart check, circumvent, disappoint, checkmate. II . n. 1.Film, flake, lamina ( of metal ).2.Contrast, background, set-off.3.Blunted rapier. Soule. Dictionary of English synonyms. Словарь английских синонимов. 2012