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definitions

foil

1
[foil]
verb (used with object)
  1. to prevent the success of; frustrate; balk: Loyal troops foiled his attempt to overthrow the government.
  2. to keep (a person) from succeeding in an enterprise, plan, etc.
noun
  1. Archaic. a defeat; check; repulse.

Origin of foil

1
1250–1300; Middle English foilen, < Anglo-French foller, Old French fuler to trample, full (cloth). See full2
Related formsfoil·a·ble, adjectiveun·foil·a·ble, adjective

Synonyms for foil

1. thwart; impede, hamper.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for foilable

foil

1
verb (tr)
  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)
noun
  1. hunting any scent that obscures the trail left by a hunted animal
  2. archaic a setback or defeat
Derived Formsfoilable, adjective

Word Origin for foil

C13 foilen to trample, from Old French fouler, from Old French fuler tread down, full ²

foil

2
noun
  1. metal in the form of very thin sheetsgold 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
verb (tr)
  1. to back or cover with foil
  2. Also: foliate architect to ornament (windows) with foils

Word Origin for foil

C14: from Old French foille, from Latin folia leaves, plural of folium

foil

3
noun
  1. a light slender flexible sword tipped by a button and usually having a bell-shaped guard

Word Origin for foil

C16: of unknown origin
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
Word Origin and History for foilable

foil

v.

c.1300, foilen "to spoil a trace or scent by running over it," irregularly from Old French fouler "trample," from Vulgar Latin *fullare "to clean cloth" (by treading on it), from Latin fullo "one who cleans cloth, fuller," of unknown origin.

Hence, "to overthrow, defeat" (1540s). Sense of "frustrate the efforts of" first recorded 1560s. Related: Foiled; foiling. Foiled again! as a cry of defeat and dismay is from at least 1847.

foil

n.

"thin sheet of metal," early 14c., from Old French fueille "leaf," from Latin folia "leaves," plural (mistaken for fem. singular) of folium "leaf" (see folio).

The sense of "one who enhances another by contrast" (1580s) is from the practice of backing a gem with metal foil to make it shine more brilliantly. The meaning "light sword used in fencing" (1590s) could be from this sense, or from foil (v.). The modern sense of "metallic food wrap" is from 1946.

Online Etymology Dictionary, © 2010 Douglas Harper