Foil may refer to:

  • Foil (metal), a quite thin sheet of metal, usually manufactured with a rolling mill machine
  • Metal leaf, a very thin sheet of decorative metal
  • Aluminium foil, a type of wrapping for food
  • Tin foil, metal foil made of tin, the direct predecessor to aluminium foil
  • Plastic foil, a thin layer of plastic material
    • Transparency (projection), as in "foil" (film over incandescent light) or "viewfoil"
Fluid dynamics
  • Foil (fluid mechanics)
    • Airfoil, a foil operating in air
    • Hydrofoil, a foil operating in water
    • Parafoil, a non-rigid airfoil, inflated during use
  • Foil bearing, a type of fluid bearing
Arts and culture
  • Foil stamping, a printmaking technique
  • Foil (band), a Seattle-based grunge rock band c.1990 - 98
  • Foil (literature), a subsidiary character who emphasizes the traits of a main character
    • A Comedic (or comic) foil, is the straight man in a comedy double act
  • The FOIL method, a way to expand the product of two first-degree polynomials ("linear factors")
  • Hydrofoil, a type of high-powered motorboat that uses underwater foils to lift its hull above the water when moving at high speeds
  • Bruce foil, a foil used on an outrigger to prevent a boat from heeling
  • Centerboard, a movable keel that functions as a foil
  • Foilboard, a surfboard using a hydrofoil
  • People in a police lineup
  • First Order Inductive Learner - a rule-based learning algorithm
  • FOIL (programming language), one of two now-defunct computer programming languages
  • Foil (fencing), one of the three weapons used in modern fencing
  • Forum of Indian Leftists, a political group of Indian intellectuals
  • Freedom of information legislation or Freedom of Information Law (FOIL)
  • Ultrasonic foil (papermaking), a type of high frequency vibrating foil involved in papermaking

Famous quotes containing the word foil:

    Like bright metal on a sullen ground,
    My reformation, glitt’ring o’er my fault,
    Shall show more goodly and attract more eyes
    Than that which hath no foil to set it off.
    William Shakespeare (1564–1616)

    Learning is, in too many cases, but a foil to common sense; a substitute for true knowledge. Books are less often made use of as “spectacles” to look at nature with, than as blinds to keep out its strong light and shifting scenery from weak eyes and indolent dispositions.... The learned are mere literary drudges.
    William Hazlitt (1778–1830)

    the stars turn slowly
    in the blue foil beside them
    like the eyes of a mild savior.
    James Tate (b. 1943)