noun cir·cum·fer·ence \ sər-ˈkəm(p)-fərn(t)s , 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


play \-ˌkəm(p)-fə-ˈren(t)-shəl\ adjective

Examples of circumference in a Sentence

  1. What is the circumference of the Earth at the equator?

  2. The circle is 38 inches in circumference.

  3. The fence marks the circumference of the field.

Recent Examples of circumference from the Web

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.

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.

Origin and Etymology of circumference

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

Other Mathematics and Statistics Terms

CIRCUMFERENCE Defined for English Language Learners



Definition of circumference for English Language Learners

  • : 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

CIRCUMFERENCE Defined for Kids


noun cir·cum·fer·ence \ sər-ˈkəm-fə-rəns , -fərns \

Definition of circumference for Students

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

Seen and Heard

What made you want to look up circumference? Please tell us where you read or heard it (including the quote, if possible).

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!


having a quality expressive of sadness

Get Word of the Day daily email!

Test Your Vocabulary

February 2018 Words of the Day Quiz

  • a-dog-in-snow-jumping-to-grab-a-heart-shaped-balloon-the-snow-and-heart-balloon-indicate-that-the-month-being-represented-is-april-and-the-dog-is-just-kinda-cute
  • Which is a synonym of sanguine?
Spell It

Can you spell these 10 commonly misspelled words?


Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!