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.
Isolated gusts in mountainous areas of Ventura and Los Angeles counties could reach up to 55 mph.
From Los Angeles Times ● Nov. 5, 2026
Rescue teams have been dispatched to the mountainous area, but the condition of those on board remains unclear.
From BBC ● Oct. 30, 2026
Fire salamanders typically inhabit damp forests, streams, and mountainous regions, where habitat destruction and fragmentation increasingly threaten their survival.
From Science Daily ● Oct. 28, 2026
In fact, Hitler Mussolini, 45, stood for the left-wing Ahora Nacion party in Queropalca in the mountainous Huanuco region.
From Barron's ● Oct. 23, 2026
They were at least 65 mountainous miles from the glider land- ing site.
From "Bomb" by Steve Sheinkin
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Get a wordDefinitions 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.