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Webster 1913 Edition
Bad lands
Bad′ lands′
.Barren regions, especially in the western United States, where horizontal strata (Tertiary deposits) have been often eroded into fantastic forms, and much intersected by cañons, and where lack of wood, water, and forage increases the difficulty of traversing the country, whence the name, first given by the Canadian French,
Mauvaises Terres
(bad lands).