- a river flowing E from E Wyoming through Nebraska to the Missouri. 431 miles (692 km) long.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for niobrara
From that point we passed down to the mouth of the Niobrara.Mary and I
Stephen Return Riggs
At its mouth, where it empties into the Niobrara, it is 165 feet wide.
A bridge has been built across the Niobrara, due north of Ainsworth.
Over it lies the bluish-gray Niobrara shale, in which natural cement is found.North Dakota
For Niobrara River (l'eau qui court), see our volume v, p. 90, note 54.