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.

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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.

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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.

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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

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verb

1. to back or cover with foil

2. Also: foliate.  architect to ornament (windows) with foils

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)

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noun

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

2. archaic a setback or defeat

foil ³ British  

/ fɔɪl /

noun

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

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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

One effort, a children’s carbonated powdered drink sold in foil packs, was scrapped after leaks in the packets caused them to burst, according to a 2014 Baltimore Magazine profile on the company.

From The Wall Street Journal

Sadie, ever loyal to my mom, had slipped it into my bag, neatly wrapped in foil, saying it was for the three of us.

From Literature

Nuñez claimed similar attacks have been foiled in other European nations, including France, Netherlands, Britain and Norway.

From BBC

Iran-linked plots have also been foiled beyond Europe, pointing to a broader campaign.

From The Wall Street Journal

Similarly, the polyester film in those shiny foil party balloons is also made from crude oil.

From The Wall Street Journal

Related Words

• counter
• curb
• elude
• frustrate
• hinder
• nullify
• prevent
• thwart