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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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
The two oceans have been separated for some three million years, ever since the isthmus of Panama rose out of the water and split them.
—Charlie Cordero, New York Times, 7 Jan. 2025
Obituaries Jimmy Carter to be honored with a state funeral before being buried next to Rosalynn
The stretch of land 50 miles long and 10 miles wide in the middle of the Panamanian isthmus had been under U.S. control since 1903, with construction of the canal starting in earnest the following year.
—Rolando Arrieta, NPR, 29 Dec. 2024
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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
The two oceans have been separated for some three million years, ever since the isthmus of Panama rose out of the water and split them.
—Charlie Cordero, New York Times, 7 Jan. 2025
Obituaries Jimmy Carter to be honored with a state funeral before being buried next to Rosalynn
The stretch of land 50 miles long and 10 miles wide in the middle of the Panamanian isthmus had been under U.S. control since 1903, with construction of the canal starting in earnest the following year.
—Rolando Arrieta, NPR, 29 Dec. 2024
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 6 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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