EXAMPLES FROM THE WEB FOR FOIL
As a foil to his austerity, therefore, she would be audaciously gay in his presence.
I ask, why is Tommy to be always the foil of Mr. Barlow to this extent?
He then, replacing the button, laid the foil down, and resumed his seat and his discourse.
Our hero was alive to the emergency, and resolved to foil him.
As one fences in the dark, instinctively, so she kept him a foil's length away.
Homer had not to wait for Beowulf to serve as a foil to his excellence.
You mean to marry her to foil van Heerden, and after—to dissolve the marriage?
It amuses her and doesn't hurt me; and, of course, I know I am meant to be her foil.
Her part seemed only as a foil to the sombre splendour of his.
I was but a waif—a foil—a thing for a coquette to play with!
c.1300, foilen "to spoil a trace or scent by running over it," irregularly from Old French fouler "trample," from Vulgar Latin *fullare "to clean cloth" (by treading on it), from Latin fullo "one who cleans cloth, fuller," of unknown origin.
Hence, "to overthrow, defeat" (1540s). Sense of "frustrate the efforts of" first recorded 1560s. Related: Foiled; foiling. Foiled again! as a cry of defeat and dismay is from at least 1847.