n.
Pronunciation: ' ye-l ō - ˌ st ō n
Function: geographical name
river 671 mi (1080 km ) NW Wyo. & S & E Mont. flowing N through Yellowstone Lake ( area 140 sq mi or 364 sq km ) & Grand Canyon of the Yellowstone in Yellowstone National Park & NE into Missouri River in NW N.Dak. near Mont. border