(geometry) Any one of a class of circles with centre at (p/q, 1/(2q²)) and radius 1/(2q²), where p/q is an irreducible fraction (i.e., p and q are coprime integers).

A stone circle or cromlech.

An electronic circuit constructed on a printed circuit board

(parapsychology) A group of spiritualists that hold sittings in order to assist confused spirits of the dead accept the fact that they are dead.

(geometry) A quarter of a circle. The shape formed from an arc that is a quarter of the circumference of a circle.

(historical, theater) A collection of venues throughout the eastern, southern, and upper Midwest areas of the United States where African-American performers were accepted despite racial segregation.

Percolating between people or places. / Freely available; not restricted in access; in general use. / (of a person) Seen in public.

(meteorology) The circulation of air in a Hadley cell.

a chain of multiple logic gates

(law) A method of analysis where decisions are based on all available information rather than bright-line rules.