adjective
-
of or relating to mountains
a mountainous region
-
like a mountain, esp in size or impressiveness
Other Word Forms
Derived 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.
Ipsos showed Fujimori dominating the capital Lima, carrying the urban vote and the coast, while Sánchez swept the rural vote and the mountainous Andes regions.
From BBC • Jun. 8, 2026
His loss of popularity is mainly due to the conflict over Nagorno-Karabakh, a mountainous enclave inside Azerbaijan that was home to 100,000 ethnic Armenians until Azerbaijan took it by force in 2023.
From BBC • Jun. 8, 2026
Laying cable on a mountainous seabed across the 1,600 miles between Ireland and Newfoundland was even tougher.
From The Wall Street Journal • Jun. 4, 2026
The company takes its name from a mountainous region spanning Argentina and Chile.
From Los Angeles Times • May 29, 2026
In the darkness, I can make out the shadowy outline of the mountainous buttes that surround us.
From "A Rover's Story" by Jasmine Warga
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.
