n.
1.being twofold
2.(physics) the property of matter and electromagnetic radiation that is characterized by the fact that some properties can be explained best by wave theory and others by particle theory
3.(geometry) the interchangeability of the roles of points and planes in the theorems of projective geometry
Idiom of the Day
thumb one's nose at (someone or something)
to look with disfavor or dislike at someone or something
The star player thumbed his nose at the fans when they began to yell at him.