circle
Americannoun
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a closed plane curve consisting of all points at a given distance from a point within it called the center. Equation: x 2 + y 2 = r 2 .
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the portion of a plane bounded by such a curve.
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any circular or ringlike object, formation, or arrangement.
a circle of dancers.
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a ring, circlet, or crown.
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the ring of a circus.
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a section of seats in a theater.
dress circle.
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the area within which something acts, exerts influence, etc.; realm; sphere.
A politician has a wide circle of influence.
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a series ending where it began, especially when perpetually repeated; cycle.
the circle of the year.
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Logic. an argument ostensibly proving a conclusion but actually assuming the conclusion or its equivalent as a premise; vicious circle.
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a complete series forming a connected whole; cycle.
the circle of the sciences.
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a number of persons bound by a common tie; coterie.
a literary circle;
a family circle.
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Government. an administrative division, especially of a province.
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Geography. a parallel of latitude.
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Astronomy.
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(formerly) the orbit of a heavenly body.
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Surveying. a glass or metal disk mounted concentrically with the spindle of a theodolite or level and graduated so that the angle at which the alidade is set may be read.
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a sphere or orb.
the circle of the earth.
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a ring of light in the sky; halo.
verb (used with object)
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to enclose in a circle; surround; encircle.
Circle the correct answer on the exam paper.
The enemy circled the hill.
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to move in a circle or circuit around; rotate or revolve around.
He circled the house cautiously.
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to change course so as to pass by or avoid collision with; bypass; evade.
The ship carefully circled the iceberg.
verb (used without object)
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to move in a circle or circuit.
The plane circled for half an hour before landing.
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Movies, Television. to iris (usually followed by in orout ).
idioms
noun
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maths a closed plane curve every point of which is equidistant from a given fixed point, the centre. Equation: ( x –h )² + ( y –k )² = r ² where r is the radius and ( h, k ) are the coordinates of the centre; area πr²; circumference: 2π r
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the figure enclosed by such a curve
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theatre the section of seats above the main level of the auditorium, usually comprising the dress circle and the upper circle
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something formed or arranged in the shape of a circle
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a group of people sharing an interest, activity, upbringing, etc; set
golf circles
a family circle
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a domain or area of activity, interest, or influence
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a circuit
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a process or chain of events or parts that forms a connected whole; cycle
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a parallel of latitude See also great circle small circle
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the ring of a circus
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one of a number of Neolithic or Bronze Age rings of standing stones, such as Stonehenge, found in Europe and thought to be associated with some form of ritual or astronomical measurement
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hockey See striking circle
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a circular argument See vicious circle
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to arrive back at one's starting point See also vicious circle
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to engage in energetic but fruitless activity
verb
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to move in a circle (around)
we circled the city by car
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(tr) to enclose in a circle; encircle
Usage
What is a basic definition of circle? In geometry, a circle is a perfectly round shape—meaning any point around its curve is the same distance from its central point. Circle commonly refers to anything that’s approximately shaped like this, even if it’s not a perfect circle in geometric terms. The letter O is a circle. As a verb, circle means to surround something or to move in a circular pattern. The word circle has several other senses as a noun and a verb. In math, a circle is one of the shapes that a student will learn about when studying geometry. A circle resembles the letter O or the symbol for zero (0). A circle consists of a closed curved line around a central point. Every point on the line is the same distance from the central point. This distance to the center is called the radius. The outer line that encloses the circle (or the length of this line) is called the circumference. Real-life example: A circle is a basic shape that’s typically taught to young children along with other simple shapes, such as triangles, squares, and rectangles. Used in a sentence: The math teacher taught the students how to measure the circumference of a circle. Outside of math, circle generally refers to any object, shape, or formation that resembles a ring. The adjective circular describes something that has the shape of a circle. Real-life examples: Wedding rings, Hula-Hoops, Cheerios, and car tires are circles. Drum circles, poetry circles, and prayer circles involve people literally arranging themselves to form a ring shape. They can also be figurative circles, with people gathering in one place for a common purpose. Used in a sentence: The children gathered in a circle around the litter of puppies. As a verb, circle means to surround something or to enclose it in a circle. Real-life example: Schoolchildren are often asked to circle the correct answer on a test. Used in a sentence: The police officers circled the building so that every exit was covered. Circle as a verb also means to move in a circle or a circular pattern around something. Real-life example: Vultures and sharks often circle around things they are planning to eat. Used in a sentence: She circled the house in search of her dropped car keys.
Synonym Usage
Circle, club, coterie, set, society are terms applied to restricted social groups. A circle may be a little group; in the plural it often suggests a whole section of society interested in one mode of life, occupation, etc.: a sewing circle; a language circle; in theatrical circles. Club implies an association with definite requirements for membership and fixed dues: an athletic club. Coterie suggests a little group closely and intimately associated because of congeniality: a literary coterie. Set refers to a number of persons of similar background, interests, etc., somewhat like a clique ( ring 1 ) but without disapproving connotations; however, it often implies wealth or interest in social activities: the country club set. A society is a group associated to further common interests of a cultural or practical kind: a Humane Society.
Other Word Forms
Derived Forms
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circlernoun
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undercirclenoun
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recircleverb
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intercircleverb (used with object)
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undercircleverb (used with object)
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uncircledadjective
Inflected Forms
Nouns
Participles
Conjugated Forms
Present
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circlesimple
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circlessimple
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have circledperfect
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has circledperfect
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am circlingprogressive
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are circlingprogressive
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is circlingprogressive
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have been circlingperfect progressive
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has been circlingperfect progressive
Past
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circledsimple
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had circledperfect
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was circlingprogressive
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were circlingprogressive
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had been circlingperfect progressive
Future
Etymology
Origin of circle
First recorded before 1000; Middle English cercle (from Old French cercle), Old English circul, both from Latin circulus, equivalent to circ(us) “circle, circular course, orbit” + -ulus diminutive ending; see circus, -ule)
Explanation
A circle is the round shape formed by all the points equidistant from a center point. This shape can be found everywhere, from the ring on your finger to the performance space in a circus (which sounds suspiciously similar, doesn’t it?). The Greek word kirkos meant circle, but the word goes back even further to the Proto-Indo-European word kirk, which meant "to bend." The noun refers to that round shape, while the verb form means to move around or surround something. Are you going to knock on the door or just circle around the house all day? If you feel like you haven't been getting anywhere with something, you might say you're "going in circles."
Vocabulary lists containing circle
Middle School Geometry, List 1
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Geometry - Introductory
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Geometry - Middle School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Still, Witkoff did not appear to be in Trump’s inner circle during his first term.
From Slate ● Jul. 22, 2026
And that, I’m afraid, brings this argument full circle once again.
From MarketWatch ● Jul. 20, 2026
Under the slogan "We are unbearable," it launched an advert showing fans from different teams sitting in a therapy circle complaining about Argentines' unbridled passion for football.
From Barron's ● Jul. 18, 2026
Maybe the Faces of Elysian Valley, a traffic circle sculpture that Huckle said “looks like Easter Island in the middle of Cypress Park.”
From Los Angeles Times ● Jul. 15, 2026
A room filled with armchairs all round it, set out in a circle.
From "Code Name Kingfisher" by Liz Kessler
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Groups sit in circles debating politics through the night.
From Barron's ● Jul. 23, 2026
While the scope of the tariffs is relatively modest—$20 billion out of more than $380 billion of Canadian exports to the U.S.—the legal justification raised eyebrows in trade circles.
From The Wall Street Journal ● Jul. 22, 2026
In New York real estate circles, Trump simply is not known for doing anything for anyone other than himself.
From Slate ● Jul. 22, 2026
LHS 1140 b circles a red dwarf star within its habitable zone.
From Science Daily ● Jul. 21, 2026
With these waves, I could easily end up going in circles and find myself back at the boat without even realizing.
From "Flying Through Water" by Mamle Wolo
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Fleetwood's form this year has been solid rather than spectacular, but The Open coming back to the Southport area for the 11th time has long been circled in his diary.
From BBC ● Jul. 14, 2026
Barzar put his comfortable black Hoka sneakers to good use as he rapidly circled the bank of self-checkout registers with a scanner gun in hand.
From The Wall Street Journal ● Jul. 8, 2026
An AFP photographer at the scene saw a heavy police presence with access to the area cordoned off, while a helicopter circled overhead.
From Barron's ● Jun. 30, 2026
The place that I kind of got circled here is Orange County.
From Los Angeles Times ● Jun. 1, 2026
Owen and George picked up their mittens and circled each other as best they could with their various injuries.
From "Two Degrees" by Alan Gratz
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It wasn’t the price that made them hesitate, but that she kept circling back to the cost.
From The Wall Street Journal ● Jul. 3, 2026
An athletic trainer followed him, circling back to the mound.
From Los Angeles Times ● Jun. 12, 2026
Just being cheap isn’t enough to attract hot money — there also has to be some belief that Wall Street vultures are circling.
From MarketWatch ● Jun. 1, 2026
Proudly displaying the coveted trophy, the players waved to the crowds from open-top buses as the Gunners travelled a five-mile loop through Islington, circling Emirates Stadium.
From BBC ● May 31, 2026
After she noticed the circling flies last night, Aunt Melissa asked my permission to throw him away.
From "South of Somewhere" by Kalena Miller
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.