adjective
-
of or relating to mountains
a mountainous region
-
like a mountain, esp in size or impressiveness
Other Word Forms
Etymology
Origin of mountainous
First recorded in 1400–50, mountainous is from the late Middle English word mounteynous. See mountain, -ous
Vocabulary lists containing mountainous
South America - Middle School
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Eastern Europe - Introductory
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East Asia - Middle School
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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.
That could bring some elevated humidity and a small chance of thunderstorms and cloud coverage in mountainous areas, but not enough to significantly lower temperatures across the region.
From Los Angeles Times ● Oct. 1, 2026
The Upper Colorado Basin, along with many mountainous regions across the U.S.
From Science Daily ● Sep. 23, 2026
The roiling mass of water, unleashed by a glacial collapse, swept down the Trishuli river, devastating a roughly 40-mile corridor of dams that were supposed to drive economic growth for mountainous Nepal.
From The Wall Street Journal ● Sep. 9, 2026
A change in wind direction at this time of year pulls warm, moist air northward from the Gulf of California and the tropical Pacific, triggering storms over mountainous terrain.
From BBC ● Sep. 1, 2026
For example, roughly one hundred million people live in adjacent areas, and six hundred million people live downstream from the pandas’ mountainous habitat.
From "Camp Panda" by Catherine Thimmesh
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.
