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.
More than a thousand people have been evacuated from their homes, mostly in the mountainous county of Hualien in Taiwan's east where authorities are monitoring two barrier dams.
From Barron's • Jul. 10, 2026
"The greatest impact is expected in Taipei, New Taipei, Keelung and Yilan, while the heaviest rainfall is forecast for mountainous areas in central and northern Taiwan."
From Barron's • Jul. 10, 2026
The area is mountainous, while Caracas is built on a plain where the sediment can amplify seismic waves and worsen damage.
From The Wall Street Journal • Jun. 25, 2026
“SR-9 is a windy mountainous road,” Lee said.
From Los Angeles Times • Jun. 24, 2026
Craning over the mountainous control panel, the pilot had a panoramic view of his plane’s snout and not much else.
From "Unbroken" by Laura Hillenbrand
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.
