adjective
-
of or relating to mountains
a mountainous region
-
like a mountain, esp in size or impressiveness
Other Word Forms
- mountainously adverb
- mountainousness noun
- nonmountainous adjective
- nonmountainously adverb
- semimountainous adjective
- semimountainously adverb
- unmountainous adjective
Etymology
Origin of mountainous
First recorded in 1400–50, mountainous is from the late Middle English word mounteynous. See mountain, -ous
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
In mountainous areas, such as Big Bear, several rattlesnakes will live together in dens.
From Los Angeles Times • Apr. 1, 2026
Locomotives need to be able to haul freight across mountainous and desert regions, in various weather conditions and temperatures.
From The Wall Street Journal • Mar. 31, 2026
After an hour on a freeway passing through suburban towns of countless rows of identical worker housing, we turned onto a more rustic road, headed into the country’s mountainous region.
From Slate • Mar. 30, 2026
But the process of collecting ballot boxes from across the mountainous country and delivering them to counting centres typically takes at least a day.
From BBC • Mar. 5, 2026
The spot Guardian found is flat and a safe area, free from obstacles such as mountainous buttes or large boulders.
From "A Rover's Story" by Jasmine Warga
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.