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.
Mountainous Kyrgyzstan and Tajikistan are also opening up new mineral deposits.
From Barron's • Nov. 6, 2025
Mountainous ridgelines and arid islands are covered in wind turbines and solar panels that today provide nearly two-thirds of the nation’s electricity.
From New York Times • May 31, 2024
Mountainous Nepal, which is regularly jolted by earthquakes, is still rebuilding after two major earthquakes in 2015 killed almost 9,000 people and destroyed whole sections of towns and cities along with centuries-old temples.
From Reuters • Oct. 4, 2023
Mountainous Nagorno-Karabakh, smaller than the U.S. state of Delaware, has significant cultural importance to both Armenians and Azeris.
From Seattle Times • Jan. 21, 2023
Mountainous piles of cages wobbled on the camels behind him.
From "The Many Assassinations of Samir, the Seller of Dreams" by Daniel Nayeri
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.
