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 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
This little isthmus also brims with rainforests and jungles teeming with all manner of beautiful and exotic wildlife—Panama is home to more than 940 species of birds as well as 220 mammals and 354 reptiles and amphibians.
—Kathleen Peddicord, Forbes, 22 Nov. 2024
Assos Assos is one more must-see spot on the island with cheerful pastel homes built on an isthmus that measures just 164 feet across.
—Stacey Leasca, Travel + Leisure, 5 Nov. 2024
Panama is a 480-mile-long strip of land, known as the isthmus, that extends from Costa Rica to Colombia, separating the Atlantic and Pacific Oceans.
—Ken Silverstein, Forbes, 1 Oct. 2024
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Rolando Arrieta, NPR, 29 Dec. 2024
This little isthmus also brims with rainforests and jungles teeming with all manner of beautiful and exotic wildlife—Panama is home to more than 940 species of birds as well as 220 mammals and 354 reptiles and amphibians.
—Kathleen Peddicord, Forbes, 22 Nov. 2024
Assos Assos is one more must-see spot on the island with cheerful pastel homes built on an isthmus that measures just 164 feet across.
—Stacey Leasca, Travel + Leisure, 5 Nov. 2024
Panama is a 480-mile-long strip of land, known as the isthmus, that extends from Costa Rica to Colombia, separating the Atlantic and Pacific Oceans.
—Ken Silverstein, Forbes, 1 Oct. 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 20 Jan. 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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