Longman Dictionary of Contemporary English
Wikipedia
A wilderness area is a region where the land is in a natural state; where impacts from human activities are minimal—that is, as a wilderness. It might also be called a wild or natural area. Especially in wealthier, industrialized nations, it has a specific legal meaning as well: as land where development is prohibited by law. Many nations have designated Wilderness Areas, including Australia, Canada, New Zealand, South Africa and the United States.
The WILD Foundation states that wilderness areas have two dimensions: they must be biologically intact and legally protected. The World Conservation Union (IUCN) classifies wilderness at two levels, Ia (Strict Nature Preserves) and Ib (Wilderness areas).
Most scientists and conservationists agree that no place on earth is completely untouched by humanity, either due to past occupation by indigenous people, or through global processes such as climate change. Activities on the margins of specific wilderness areas, such as fire suppression and the interruption of animal migration, also affect the interior of wildernesses.