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
fed up with (someone or something)
to be disgusted or bored with someone or something
I think that the worker is fed up with the constant complaints of his boss.