mountainous

adjective

moun·tain·ous ˈmau̇n-tə-nəs

ˈmau̇nt-nəs

Synonyms of mountainous

: containing many mountains

mountainous wilderness

: resembling a mountain : huge

a stormy ocean with mountainous waves

mountainously adverb

mountainousness noun

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.

The coming days are more hilly than truly mountainous, though that may not stop Pogačar from forcing gaps, with stage nine’s ascent in Aitana, in Alicante, part of a day featuring 5000m of elevation. — Jacob Whitehead, New York Times, 20 Aug. 2026 Ramping oil output is the ticket to restructuring Venezuela’s mountainous $250 billion debt load, equal to roughly 150% of GDP, the highest number in Latin America and fourth in the world. — Shawn Tully, Fortune, 20 Aug. 2026 This park also falls along the Rio Grande and includes mountainous terrain with tall cliffs and a desert landscape. — Ashley Killough, CNN Money, 19 Aug. 2026 To explore Great Basin above ground, hit the 12-mile Wheeler Peak Scenic Drive, a mountainous road winding up to 10,000 feet of elevation, with trails, lakes, and pine groves to admire along the way. — Stephanie Vermillion, Travel + Leisure, 18 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

See more words from the same century

Cite this Entry

Style

“Mountainous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mountainous. Accessed 27 Aug. 2026.

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Kids Definition

mountainous

adjective

moun·tain·ous ˈmau̇nt-ᵊn-əs

-nəs

: having many mountains

: resembling a mountain : huge

mountainous

adjective

Synonyms of mountainous

Examples of mountainous in a Sentence

Word History

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Cite this Entry

Kids Definition

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