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

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Other Words from circumference

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

Synonyms for circumference



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Did You Know?

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.
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Recent Examples on the Web

The classic symptoms of sleep apnea may include snoring, having a large neck circumference, obesity and waking up tired. Beth Mlady,, "Middleburg Heights store offers options for sleep apnea sufferers," 30 Aug. 2019 Ancient mathematicians, for instance, recognized that the elusive ratio of a circle’s circumference to its diameter can be well approximated by the fraction 22/7. Wired, "A Major Proof Shows How to Approximate Numbers Like Pi," 18 Aug. 2019 Second, the pattern of injury does not appear to be frostbite, as the cold causes vasoconstriction that would be most prominent in the toes and the cold air touches more of the circumference of toes. San Diego Union-Tribune, "Not technically frostbite, but Antonio Brown’s feet might have gotten worse in cryotherapy," 7 Aug. 2019 At each level, there is a network of ring beams the entire circumference of the Sphere. Melinda Sheckells, Billboard, "Las Vegas' MSG Sphere at The Venetian Will Be An 'Architectural Marvel': Photos," 24 July 2019 Pi, the ratio of the circumference of a circle to its diameter, represents mystery itself. Ephrat Livni, Quartz, "Two new books will transform your everyday understanding of math," 17 June 2019 Most noise-reducing tires have strips of foam lining their inner circumference, which dampens the problem. Nick Stockton, WIRED, "Bridgestone's New Tire Makes Driving Electric as Quiet as It Should Be," 5 June 2019 The two circles hang at the same point on their circumference, so the big circle always carries the little circle inside it. Chicago Tribune,, "Algren Award finalist: "Nothing Less Than 20,000 Watts" by Susan Finch," 2 June 2018 The drill bit used to create the hole was misaligned, leaving the tube about half a millimeter too thin along one small portion of its circumference. Roma Agrawal, New York Times, "Under Modernity’s Hood: Precision Engineering," 14 May 2018

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.

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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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Statistics for circumference

Last Updated

9 Sep 2019

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Time Traveler for circumference

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

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More Definitions for circumference



English Language Learners Definition of circumference

: the length of a line that goes around something or that makes a circle or other round shape
: the outer edge of a shape or area


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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Comments on circumference

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miscellaneous remnants or debris

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