Circle

From Latin circulus. Replaced Middle English cercle, from Old French cercle, from the same Latin source.

Full definition of circle

(plural circles)

(geometry) A two-dimensional geometric figure, a line, consisting of the set of all those points in a plane that are equally distant from another point.The set of all points (x, y) such that (x-1)² + y² = r² is a circle of radius r around the point (1, 0).
A two-dimensional geometric figure, a disk, consisting of the set of all those points of a plane at a distance less than or equal to a fixed distance from another point.
Any thin three-dimensional equivalent of the geometric figures.Put on your dunce-cap and sit down on that circle.
A curve that more or less forms part or all of a circle.move in a circle
Orbit.
A specific group of persons.inner circlecircle of friends

MacaulayAs his name gradually became known, the circle of his acquaintance widened.
1907, w, The Younger Set Chapter 6, â€œI don't mean all of your friendsâ€”only a small proportionâ€”which, however, connects your circle with that deadly, idle, brainless bunchâ€”the insolent chatterers at the opera, the gorged dowagers, â€¦â€‰!â€
1922, Margery Williams, The Velveteen RabbitThe Rabbit could not claim to be a model of anything, for he didnâ€™t know that real rabbits existed; he thought they were all stuffed with sawdust like himself, and he understood that sawdust was quite out-of-date and should never be mentioned in modern circles.

(cricket) A line comprising two semicircles of 30 yards radius centred on the wickets joined by straight lines parallel to the pitch used to enforce field restrictions in a one-day match.
(Wicca) A ritual circle that is cast three times deosil and closes three times widdershins either in the air with a wand or literally with stones or other items used for worship.
(South Africa) A traffic circle or roundabout.

2011, Charles E. Webb, Downfall and Freedom (page 120)He arrived at the lakefront and drove around the circle where the amusement park and beach used to be when he was a kid...

(astronomy) An instrument of observation, whose graduated limb consists of an entire circle. When fixed to a wall in an observatory, it is called a mural circle; when mounted with a telescope on an axis and in Y's, in the plane of the meridian, a meridian or transit circle; when involving the principle of reflection, like the sextant, a reflecting circle; and when that of repeating an angle several times continuously along the graduated limb, a repeating circle.
A series ending where it begins, and repeating itself.

(logic) A form of argument in which two or more unproved statements are used to prove each other; inconclusive reasoning.

GlanvillThat heavy bodies descend by gravity; and, again, that gravity is a quality whereby a heavy body descends, is an impertinent circle and teaches nothing.

A territorial division or district.The ten Circles of the Holy Roman Empire were those principalities or provinces which had seats in the German Diet.

(two-dimensional outline geometric figure) coil not in mathematical use, ring not in mathematical use, loop not in mathematical use
(two-dimensional solid geometric figure) disc/disk in mathematical and general use, round (not in mathematical use; UK & Commonwealth only)
(curve) arc, curve
(orbit) orbit
(a specific group of persons) bunch, gang, group

(transitive) To place or mark a circle around.Circle the jobs that you are interested in applying for.
(intransitive) To travel in circles.Vultures circled overhead.