semicircle

noun

semi·​cir·​cle ˈse-mē-ˌsər-kəl How to pronounce semicircle (audio)
ˈse-ˌmī-, 
-mi-
Synonyms of semicirclenext
1
: a half of a circle
2
: an object or arrangement of objects in the form of a half circle
semicircular
ˌse-mē-ˈsər-kyə-lər How to pronounce semicircle (audio)
ˌse-ˌmī-, 
-mi-
adjective

Examples of semicircle in a Sentence

The children sat in a semicircle. The houses are built in a semicircle.
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 work trucks continued on, but much of the Border Patrol force remained, forming a semicircle around the camp with Mexican state police closing the loop on the other side of the line. — Ryan Devereaux, ProPublica, 10 Oct. 2026 Take one semicircle and bring the two straight edges together, slightly overlapping them to form a cone. — ABC News, 5 Oct. 2026 Lindblom Math and Science Academy students sat in a semicircle with some of the University of Illinois System’s top officials, notebooks in front of them and pens in hand. — Kate Perez, Chicago Tribune, 25 Sep. 2026 Construction workers in reflective vests and hardhats formed a semicircle for the cameras. — Antonia Hitchens, New Yorker, 4 Sep. 2026 See All Example Sentences for semicircle

Word History

Etymology

Latin semicirculus, from semi- + circulus circle

First Known Use

1526, in the meaning defined at sense 1

Time Traveler
The first known use of semicircle was in 1526

Rhymes for semicircle

See All Rhymes for semicircle

Browse Nearby Words

semichorus
semicircle
semicircular
See all Nearby Words

Cite this Entry

“Semicircle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/semicircle. Accessed 20 Oct. 2026.

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Kids Definition

semicircle

noun
semi·​cir·​cle ˈsem-i-ˌsər-kəl How to pronounce semicircle (audio)
1
: half of a circle
2
: an object or arrangement of objects in the form of a half circle
semicircular
ˌsem-i-ˈsər-kyə-lər How to pronounce semicircle (audio)
adjective

More from Merriam-Webster on semicircle

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