Geometry. Forming, or pertaining to, an umbilicus.

Mathematics. Relating to or referred to a pole (pole, n.2 8); of the nature of a polar (sense B. 2).

Of or belonging to the umbilicus.

Joining, connecting.

Geometry. Pertaining or relating to the points called stigmata: see stigma, n. 7 and B. 4.

Geometry. Having, relating to, or of the nature of, a cusp: see cusp, n. 4.

Mathematics. Of, relating to, or constituting a trope (trope, n. 9). rare.

Having a cusp or cusps.

Meeting in a point, concurrent.

Mathematics. Of a set of points: not containing any of its boundary points; having a closed set as its complement. Of an interval in the real line…

Mathematics. Of a set of points: closed, and such that every neighbourhood of each point of the set contains at least one other point of the set.

Mathematics. Of a set of points: containing all its limit points. Of an interval: containing all its end points.