2. A circular course, circuit, or orbit: a satellite's circle around the earth.
3. A curved section or tier of seats in a theater.
4. A process, series, or process that finishes at its starting point or continuously repeats itself; a cycle.
5. A group of people sharing a common interest, profession, activity, social background, or achievement: well-known in artistic circles.
6. A territorial or administrative division, especially of a province, in some European countries.
2. An arrangement of people or things that forms a circumference: The campers formed a circle around the campfire.
2. To move or to go around someone or something: The pilot had to circle above the airport before he could land.
The pioneers had to circle their wagons so they could defend themselves better if there were an attack.
When Blake was at camp, he would sit in a circle and look up at the sky and he could see the planes circle overhead while they waited for their turns to land at the local airport.
That reminded Blake of the time when he was a child watching skywriters flying overhead and drawing circles and other letters in the sky with the smoke from their planes.
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A circle is commonly described by its radius, a straight line extending from the center of the circle to any point on the perimeter; and its diameter, a straight line extending from a point on the perimeter, through the center, to a point on the perimeter on the other side of the circle or it is expressed as "twice the radius".