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v. Simple past tense and past participle of foil.

In medieval architecture, having foils: as, a foiled arch.

adj. disappointingly unsuccessful

"Former Lashkar trainees had also been prosecuted in foiled plots against New York, London and Australia."

fool   

Gould    cooled    goold    overruled    pooled    retooled    ruled    schooled    supercooled    tooled