cir·​cum·​fer·​ence | \ sər-ˈkəm(p)-fərn(t)s How to pronounce circumference (audio) , sə-, -f(ə-)rən(t)s \

Definition of circumference

1 : the perimeter of a circle The circle measures 22 inches in circumference.
2 : the external boundary or surface of a figure or object : periphery from the center to the circumference of the sphere

Other Words from circumference

circumferential \ sər-​ˌkəm(p)-​fə-​ˈren(t)-​shəl How to pronounce circumference (audio) , sə-​ \ adjective

Synonyms for circumference


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Attempts have been made to measure the circumference of the earth since the time of Aristotle. The calculation that Columbus was relying on led him to think he could reach China by sailing west more quickly than by sailing east. But that measurement had calculated the earth's circumference as about a quarter too small, and the rest is history. Columbus wasn't the only one who got it wrong; many later attempts continued to produce different measurements for the earth's circumference—even though the Greeks had calculated it correctly way back in the 3rd century B.C.

Examples of circumference in a Sentence

What is the circumference of the Earth at the equator? The circle is 38 inches in circumference. The fence marks the circumference of the field.
Recent Examples on the Web Consisting of a ring 27 kilometers (16.7 miles) in circumference, the machine is made of superconducting magnets chilled to ‑271.3°C (-456 F) -- which is colder than outer space. Sara Spary, CNN, 22 Apr. 2022 The cumulative distance traveled by this gazelle during the study period corresponded to almost half of the circumference of Earth’s equator. Robin Lloyd, Scientific American, 7 Apr. 2022 Today's the annual celebration of the mathematical constant called pi, the ratio of a circle circumference to its diameter and the ratio is rounded to today's date 3.14. Taylor Wilson, USA TODAY, 14 Mar. 2022 Chipperfield’s own contribution has been a collection of old granite stones carved out around the circumference by the local fishermen, who would use them as weights. Sarah Medford, WSJ, 9 Mar. 2022 The poplar, which had a circumference of around 157 inches and may have been more than 100 years old, would not easily be replaced even by 100 theoretical trees, Eutsler said. Washington Post, 4 Mar. 2022 The patio curves around about 1/4 of the circumference of the tree about 40 feet out from the trunk. oregonlive, 26 Feb. 2022 Researchers in China found that older people who practiced yoga for a year shed about a centimeter off their waist circumference—a key marker of belly fat. Julie Stewart, Men's Health, 28 Mar. 2022 To calculate the diameter of the trunk, measure the distance around the trunk, its circumference, and divide by 3.14, also known as Pi. oregonlive, 26 Feb. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'circumference.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of circumference

14th century, in the meaning defined at sense 1

History and Etymology for circumference

Middle English, from Middle French & Latin; Middle French, from Latin circumferentia, from circumferre to carry around, from circum- + ferre to carry — more at bear

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The first known use of circumference was in the 14th century

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Last Updated

20 May 2022

Cite this Entry

“Circumference.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for circumference


cir·​cum·​fer·​ence | \ sər-ˈkəm-fə-rəns How to pronounce circumference (audio) , -fərns \

Kids Definition of circumference

1 : the line that goes around a circle
2 : a boundary line enclosing an area A fence marks the circumference of the yard.
3 : the distance around something


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