Of, relating to, or being any of several modern geometries that are not based on the postulates of Euclid.
Designating or of a geometry that rejects any of the postulates of Euclidean geometry, esp. the postulate that through a given point only one line can be drawn parallel to another line that does not contain the given point.
Relating to any of several modern geometries that are based on a set of postulates other than the set proposed by Euclid, especially one in which all of the postulates of Euclidean geometry hold except the parallel postulate .
Of, or relating to non-Euclidean geometry.