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 bridge is part of the Xichang–Shangri-La Expressway, where construction across mountainous terrain requires precise lifting and positioning of large structural components. — Kaif Shaikh, Interesting Engineering, 24 Oct. 2026 One person was killed and 94 were injured in Taiwan, where the government said almost 1,300 people had been evacuated from mountainous areas. — Reuters, NBC news, 23 Oct. 2026 Successive generations continue the migration through the United States and Canada, and in the fall their descendants make the return journey to the same mountainous region of Mexico. — Encyclopedia Britannica, 23 Oct. 2026 Hop on the #6 double-decker from Central to Stanley beach, which lurches around Hong Kong Island's mountainous southern South China Sea coast (sit upstairs on the right-hand side). — Lee Cobaj, Condé Nast Traveler, 20 Oct. 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 Oct. 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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