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Synonyms

foil

1 American  
[foil] / fɔɪl /

verb (used with object)

  1. to prevent the success of; frustrate; balk.

    Loyal troops foiled his attempt to overthrow the government.

    Synonyms:
    hamper , impede , thwart
  2. to keep (a person) from succeeding in an enterprise, plan, etc.


noun

  1. Archaic.  a defeat; check; repulse.

foil 2 American  
[foil] / fɔɪl /

noun

  1. metal in the form of very thin sheets.

    aluminum foil.

  2. the metallic backing applied to glass to form a mirror.

  3. a thin layer of metal placed under a gem in a closed setting to improve its color or brilliancy.

  4. a person or thing that makes another seem better by contrast.

    The straight man was an able foil to the comic.

    Synonyms:
    counterpart , complement , contrast
  5. Architecture.  an arc or a rounded space between cusps, as in the tracery of a window or other ornamentation.

  6. an airfoil or hydrofoil.


verb (used with object)

  1. to cover or back with foil.

  2. to set off by contrast.

foil 3 American  
[foil] / fɔɪl /

noun

Fencing.
  1. a flexible four-sided rapier having a blunt point.

  2. foils, the art or practice of fencing with this weapon, points being made by touching the trunk of the opponent's body with the tip of the weapon.


foil 1 British  
/ fɔɪl /

noun

  1. metal in the form of very thin sheets

    gold foil

    tin foil

  2. the thin metallic sheet forming the backing of a mirror

  3. a thin leaf of shiny metal set under a gemstone to add brightness or colour

  4. a person or thing that gives contrast to another

  5. architect a small arc between cusps, esp as used in Gothic window tracery

  6. short for aerofoil hydrofoil

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to back or cover with foil

  2. Also: foliatearchitect to ornament (windows) with foils

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
foil 2 British  
/ fɔɪl /

verb

  1. to baffle or frustrate (a person, attempt, etc)

  2. hunting (of hounds, hunters, etc) to obliterate the scent left by a hunted animal or (of a hunted animal) to run back over its own trail

  3. archaic  to repulse or defeat (an attack or assailant)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. hunting any scent that obscures the trail left by a hunted animal

  2. archaic  a setback or defeat

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
foil 3 British  
/ fɔɪl /

noun

  1. a light slender flexible sword tipped by a button and usually having a bell-shaped guard

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • foilable adjective
  • unfoilable adjective

Etymology

Origin of foil1

First recorded in 1250–1300; Middle English foilen, fuylen “to trample, oppress, torment, mortify (the flesh),” irregular variant of fullen “to trample, full (cloth),” from Anglo-French foller, Old French fuler, from Vulgar Latin fullāre, from Latin fullō “fuller, launderer”; full 2

Origin of foil2

First recorded in 1350–1400; Middle English foil, foille “leaf (of a plant or a book),” from Old French fuelle, fueille, foille (from Latin folia “leaves,” reinterpreted as a feminine singular noun) and from Old French fuel, fueil, foil (from Latin folium “leaf of a plant, blade”)

Origin of foil3

First recorded in 1585–95; origin uncertain

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"Some of our volunteers have dug up phones wrapped in tin foil," Ms Gates added.

From BBC

The aluminum ingredient in vaccines isn’t the same as what’s in kitchen foil.

From The Wall Street Journal

Buddy’s plan gets foiled when Odd, confronted with his crime, quietly admits it, returns the loot, and leaves the house.

From The Wall Street Journal

It fits a standard glass baking dish or a simple foil tray, and either way, it helps everything arrive — and stay — exactly as it should.

From Salon

However, Ukraine's SBU security service had been watching and foiled the attack.

From BBC