adjective
-
of or relating to mountains
a mountainous region
-
like a mountain, esp in size or impressiveness
Other Word Forms
- mountainously adverb
- mountainousness noun
- nonmountainous adjective
- nonmountainously adverb
- semimountainous adjective
- semimountainously adverb
- unmountainous adjective
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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Mexico - Introductory
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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.
Drones struggle to count items that are covered or hiding, such as cattle in mountainous terrains, and are largely ineffective indoors.
From The Wall Street Journal • Apr. 7, 2026
Following this, both the US and Iran scrambled to locate the missing crew member in a mountainous region of southwestern Iran.
From BBC • Apr. 5, 2026
Both the US and Iran scrambled to locate the remaining US serviceman in a mountainous region of south-western Iran.
From BBC • Apr. 5, 2026
The area's mountainous geography makes it doubly vulnerable.
From Barron's • Apr. 3, 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.
