Pronunciation

change

Singular
foil

Plural
foils

  1. A foil is a sword used in the sport of fencing.
    He struck his opponent three times with his foil.
  2. Foil is a very thin sheet of metal.
    He wrapped his sandwich in aluminium foil.

Plain form
foil

Third-person singular
foils

Past tense
foiled

Past participle
foiled

Present participle
foiling

  1. To foil is to stop somebody who is trying to do something.
    The guard was able to foil the bad man from hurting the little girl.