"Circle dance" is the most common name for a style of traditional dance usually done in a circle without partners to musical accompaniment.

Dancing in a circle is an ancient tradition common to many cultures for marking special occasions, strengthening community and encouraging togetherness. The circle is probably the oldest known dance formation. It is found even today in the community dances of many cultures, including Greek (Greek dances surviving from ancient Greece (chorea)), African, Eastern European, Israeli (see Jewish dance and Israeli folk dancing), South Slavic, Irish Celtic, Breton, Catalan (sardana), South American and North American Indian. It is also used, in its more meditative form, in worship within various religious traditions, including, for example, the Church of England and other Anglican Churches and the Islamic Haḍra dances.

Modern circle dance mixes traditional folk dances, mainly from European or Near-Eastern sources, with recently choreographed ones to a variety of music both ancient and modern and they draw on a rich and diverse dance tradition. There is also a growing repertoire of new dances to classical music and contemporary songs.

A circle is a simple shape of Euclidean geometry consisting of those points in a plane that are equidistant from a given point, the centre. The distance between any of the points and the centre is called the radius.

Circles are simple closed curves which divide the plane into two regions: an interior and an exterior. In everyday use, the term "circle" may be used interchangeably to refer to either the boundary of the figure, or to the whole figure including its interior; in strict technical usage, the circle is the former and the latter is called a disk.

A circle can be defined as the curve traced out by a point that moves so that its distance from a given point is constant.

A circle may also be defined as a special ellipse in which the two foci are coincident and the eccentricity is 0. Circles are conic sections attained when a right circular cone is intersected by a plane perpendicular to the axis of the cone.

A circle's diameter is the length of a line segment whose endpoints lie on the circle and which passes through the centre. This is the largest distance between any two points on the circle. The diameter of a circle is twice the radius, or distance from the centre to the circle's boundary. The terms "diameter" and "radius" also refer to the line segments which fit these descriptions. The circumference is the distance around the outside of a circle.

Dance is a type of art that generally refers to movement of the body, usually rhythmic and to music, performed in many different cultures and used as a form of expression, social interaction or presented in a spiritual or performance setting.

Dance may also be regarded as a form of nonverbal communication between humans, and is also performed by other animals (bee dance, patterns of behaviour such as a mating dance). Gymnastics, figure skating and synchronized swimming are sports that incorporate dance, while martial arts kata are often compared to dances. Motion in ordinarily inanimate objects may also be described as dances (the leaves danced in the wind).

Definitions of what constitutes dance are dependent on social, cultural, aesthetic, artistic and moral constraints and range from functional movement (such as folk dance) to virtuoso techniques such as ballet. Dance can be participatory, social or performed for an audience. It can also be ceremonial, competitive or erotic. Dance movements may be without significance in themselves, such as in ballet or European folk dance, or have a gestural vocabulary/symbolic system as in many Asian dances. Dance can embody or express ideas, emotions or tell a story.