Pronunciation: (täl'veg, -vāk), [key]
1. a line, as drawn on a map, connecting the lowest points of a valley.
2. Chiefly Internat. Law.the middle of the main navigable channel of a waterway that serves as a boundary line between states.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.