'Niagara River' definitions:
Definition of 'Niagara River'
From: WordNet
noun
A river flowing from Lake Erie into Lake Ontario; forms boundary between Ontario and New York [syn: Niagara, Niagara River]
Definition of 'Niagara River'
From: GCIDE
- Niagara \Niagara\, Niagara River \Niagara River\prop. n. A river flowing from Lake Erie into Lake Ontario, which forms the boundary between Ontario and New York. [WordNet 1.5]