mountainous

adjective

moun·​tain·​ous ˈmau̇n-tə-nəs How to pronounce mountainous (audio)
ˈmau̇nt-nəs
Synonyms of mountainousnext
1
: containing many mountains
mountainous wilderness
2
: resembling a mountain : huge
a stormy ocean with mountainous waves
mountainously adverb
mountainousness noun

Synonyms of mountainous

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Examples of mountainous in a Sentence

the seemingly mountainous obstacles he had to overcome while growing up
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Gangs continue to hold dozens of residents seized during a recent attack on the mountainous community of Kenscoff, where gunmen shot people to death and burned others alive in their homes. — Jacqueline Charles, Miami Herald, 3 Sep. 2026 As the second most mountainous municipality in Spain, Castellón’s skyline is decidedly jagged. — Condé Nast Traveler, 3 Sep. 2026 Just 10 days later, Hurricane Ivan dumped more rain in an unprecedented double whammy for the mountainous region far from the coast. — Ren Larson, ProPublica, 2 Sep. 2026 Oddly enough, this is actually one of the least scary activities in Shiniuzhai's mountainous area. — New Atlas, 1 Sep. 2026 See All Example Sentences for mountainous

Word History

Etymology

Middle English mounteynous, borrowed from Anglo-French muntaignus, from muntaigne, mountaigne mountain + -us -ous

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of mountainous was in the 14th century

Browse Nearby Words

mountain of Venus
mountainous
mountainousness
See all Nearby Words

Cite this Entry

“Mountainous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mountainous. Accessed 4 Sep. 2026.

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Kids Definition

mountainous

adjective
moun·​tain·​ous ˈmau̇nt-ᵊn-əs How to pronounce mountainous (audio)
-nəs
1
: having many mountains
2
: resembling a mountain : huge
Last Updated: - Updated example sentences
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