1. (

• foil ,

) a piece of thin and flexible sheet metal; "the photographic film was wrapped in foil" ;

2. (

• foil ,
• enhancer

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

3. (

• hydrofoil ,
• foil ,

) 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" ;

4. (

• foil ,
• transparency ,

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

5. (

• foil

) a light slender flexible sword tipped by a button ;

1. (

• foil

) enhance by contrast; "In this picture, the figures are foiled against the background" ;

2. (

• thwart ,
• queer ,
• spoil ,
• scotch ,
• foil ,
• cross ,
• frustrate ,
• baffle ,
• bilk ,

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

3. (

• foil

) cover or back with foil; "foil mirrors" ;