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.
Rescue teams with search dogs had been dispatched to the mountainous area in Haixi prefecture on the Tibetan plateau. — ABC News, 16 June 2026 Because the island is so steep and mountainous, even shorter routes can involve serious climbs and uneven terrain. — Chadner Navarro, Travel + Leisure, 30 June 2026 This tiny, mountainous country, north of Greece and south of Montenegro, is a haven for outdoorsy types thanks to epic hiking trails through the Albanian Alps. — Sarah Sekula, USA Today, 26 June 2026 Northern Spain’s mountainous scenery surrounds Oviedo and boasts lower levels of light pollution than other metropolitan centers. — Kaitlyn McInnis, Forbes.com, 30 June 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 7 Jul. 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

More from Merriam-Webster on mountainous

Nglish: Translation of mountainous for Spanish Speakers

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