foil

a piece of thin and flexible sheet metal; "the photographic film was wrapped in foil"

anything that serves by contrast to call attention to another thing's good qualities; "pretty girls like plain friends as foils"

a device consisting of a flat or curved piece (as a metal plate) so that its surface reacts to the water it is passing through; "the fins of a fish act as hydrofoils"

picture consisting of a positive photograph or drawing on a transparent base; viewed with a projector

a light slender flexible sword tipped by a button

enhance by contrast; "In this picture, the figures are foiled against the background"

hinder or prevent (the efforts, plans, or desires) of; "What ultimately frustrated every challenger was Ruth's amazing September surge"; "foil your opponent"

cover or back with foil; "foil mirrors"