1
: a narrow strip of land connecting two larger land areas
2
: a narrow anatomical part or passage connecting two larger structures or cavities
Examples of isthmus in a Sentence
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The waterway was cleaved across the most narrow section of the Panamanian isthmus in the late 1800s and early 1900s, by French and then U.S. engineers.
—
Tracy Wilkinson, Los Angeles Times, 31 Jan. 2025
At the beginning of the 20th century, the isthmus of Panama was part of Colombia.
—Lisa Friedman, New York Times, 8 Jan. 2025
For generations, outsiders had considered the narrow isthmus to be the perfect spot for a trans-oceanic canal that would shorten the sea voyage by thousands of miles.
—Patrick Oppmann, CNN, 20 Jan. 2025
Because Crimea is connected to the Eurasian continent only by a narrow, vulnerable isthmus and a bridge, once Ukrainian troops enter the region, the remaining Russian forces will be trapped, making Russian military sites even more vulnerable to Ukrainian strikes.
—Andriy Zagorodnyuk, Foreign Affairs, 2 Jan. 2023
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Tracy Wilkinson, Los Angeles Times, 31 Jan. 2025
At the beginning of the 20th century, the isthmus of Panama was part of Colombia.
—Lisa Friedman, New York Times, 8 Jan. 2025
For generations, outsiders had considered the narrow isthmus to be the perfect spot for a trans-oceanic canal that would shorten the sea voyage by thousands of miles.
—Patrick Oppmann, CNN, 20 Jan. 2025
Because Crimea is connected to the Eurasian continent only by a narrow, vulnerable isthmus and a bridge, once Ukrainian troops enter the region, the remaining Russian forces will be trapped, making Russian military sites even more vulnerable to Ukrainian strikes.
—Andriy Zagorodnyuk, Foreign Affairs, 2 Jan. 2023
See all Example Sentences for isthmus
Dictionary Entries Near isthmus
Cite this Entry
“Isthmus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isthmus. Accessed 21 Feb. 2025.
Copy CitationKids Definition
isthmus
noun
isth·mus
ˈis-məs 
: a narrow strip of land connecting two larger land areas
Medical Definition
isthmus
noun
isth·mus
ˈis-məs
: a contracted anatomical part or passage connecting two larger structures or cavities: as
a
: an embryonic constriction separating the midbrain from the hindbrain
b
: the lower portion of the uterine corpus
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