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.
More than 500 foreigners from 32 countries are among those still unaccounted for in the rugged mountainous region, which is popular with pilgrims and trekkers. — Josh Feldman, NBC news, 27 Aug. 2026 That could set off flash flooding in some of the more mountainous spots, the hurricane center warned. — Alex Harris, Miami Herald, 27 Aug. 2026 Nepal's mountainous terrain, dotted with deep valleys and narrow gorges, makes rescue and relief operations challenging. — Arshad R. Zargar, CBS News, 26 Aug. 2026 Wind gusts of up to 30 mph were reported in the Reno area and gusts up to 40 mph were reported on Saturday in the mountainous areas and on downslopes where the Hawk Fire is burning. — Kyle Reiman, ABC News, 23 Aug. 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 2 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
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