noun:

1. A specific group of persons; especially one who shares a common interest.
2. Compass; circuit; enclosure.
3. 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.
4. A form of argument in which two or more unproved statements are used to prove each other; inconclusive reasoning.
5. 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 (radius) from a given point.
6. A traffic circle or roundabout.
7. Any thin three-dimensional equivalent of the geometric figures.
8. The orbit of an astronomical body.
9. A series ending where it begins, and repeating itself.
10. Indirect form of words; circumlocution.
11. Any shape, curve or arrangement of objects that approximates to or resembles the geometric figures.
12. A two-dimensional geometric figure, a line, consisting of the set of all those points in a plane that are equally distant from a given point (center).
13. 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.
14. 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.
15. A bagginess of the skin below the eyes from lack of sleep.
16. A curve that more or less forms part or all of a circle.
17. A territorial division or district.

verb:

1. To place or mark a circle around.
2. To travel around along a curved path.
3. To travel in circles.
4. To surround.

name:

1. The Circle line of the London Underground, originally the Inner Circle.
2. A census-designated place in Yukon-Koyukuk Census Area, Alaska, United States. Erroneously thought to be on the Arctic Circle, which is 50 miles further north.
3. A town, the county seat of McCone County, Montana, United States. Named after a cattle brand in the form of a circle.