EntityQ3926560· pop 27· linked from 45 articlesquadrantSign in to saveregion of the plane defined by the axes of a two-dimensional Cartesian systemConnectionslineEntityRoman numeralsEntityplaneEntityCartesian coordinate systemEntitycircular sectorEntitymnemonicEntityMathWorldEntityEric W. WeissteinEntityclockwise directionEntityPlanetMathEntityoctantEntityorthantEntityupper half-planeEntitydomainEntitymnemonics in trigonometryEntityCategoriesEuclidean plane geometry