Foil is defined as a thin piece of metal, or a sword used in fencing.(noun)
To foil is defined as to keep something from happening.(verb)
An example of foil is when your mom catches you sneaking out to go to a party.
See foil in Webster's New World College Dictionary
Origin: ME foilen < OFr fuler, to trample on, subdue: see full
Origin: ME < OFr fuil (Fr feuille), a leaf < L folia < folium, leaf: see foliate
Origin: < ?
See foil in American Heritage Dictionary 4
transitive verb foiled, foil·ing, foils
Origin: Middle English foilen, to trample, defile
Origin: , variant of filen, to defile; see file3.
Origin: Middle English
Origin: , from Old French foille
Origin: , from Latin folia
Origin: , pl. of folium, leaf; see bhel-3 in Indo-European roots.
Origin: Origin unknown.
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