foil
n. countablen. a person or thing that makes another person's qualities look better or more obvious because they are so different. You often see this in stories where a very serious character has a funny friend.
n. a person or thing that contrasts with and so emphasizes and enhances the qualities of another. Often used in literary analysis to describe a character whose traits highlight the protagonist's nature.
The serious detective needs a funny partner to act as a foil.
In the novel, the protagonist's cautious nature is highlighted by his adventurous friend, who serves as a perfect foil.
The architect used rough, unpolished stone as a foil to the sleek glass panels, creating a visual tension that defined the building's facade.
From Middle English foyle, from Middle French fueille, from Old French fueille (“plant leaf”), from Late Latin folia, the plural of folium, mistaken as a singular feminine. The literary sense is from the practice of backing a gem with metal foil to make it shine more brilliantly. Doublet of folio and folium, distantly also with phyllo and phyllon.
From Middle English foilen (“spoil a scent trail by crossing it”), from Old French fouler (“tread on, trample”), ultimately from Latin fullō (“to trample, full”).
From French foulis.
From mnemonic acronym FOIL (“First Outside Inside Last”).
See file.
Often used with the preposition 'to' ('a foil to').