(geometry) Any of the three circles inside a given triangle such that each circle is tangent to the others and to two sides of the triangle.

plural of Malfatti circle

plural of circle pit

(dance, music) A dance at a concert where participants mosh in a circular path, leaving the centre clear.

A social circle on the Internet.

plural of e-circle

A phenomenon that occurs on rivers during winter, where floating ice caught in an eddying flow will rotate around, knocking off its distant edges, forming a floating revolving circular disk, slowing turning under the influence of the underlying vortex current; when the temperature conditions are not too warm, leading to ice breakup and fragility, and not too cool, freezing over the entire surface.

plural of hour circle

(astronomy) The great circle through an object whose location is to be determined and the two celestial poles.

(of a black hole) Synonym of photon sphere