foil

Noun

• a light slender flexible sword tipped by a button

• picture consisting of a positive photograph or drawing on a transparent base; viewed with a projector

• a device consisting of a flat or curved piece (as a metal plate) so that its surface reacts to the water it is passing through
  • the fins of a fish act as hydrofoils
    

• anything that serves by contrast to call attention to another thing's good qualities
  • pretty girls like plain friends as foils
    

• a piece of thin and flexible sheet metal
  • the photographic film was wrapped in foil
    

Verb

• cover or back with foil
  • foil mirrors
    

• hinder or prevent (the efforts, plans, or desires) of
  • What ultimately frustrated every challenger was Ruth's amazing September surge
    
  • foil your opponent
    

• enhance by contrast
  • In this picture, the figures are foiled against the background
    

Related words

• Synonyms: 
  transparency , hydrofoil , enhancer , thwart , queer , spoil , scotch , cross , frustrate , baffle , bilk