umbilicus

noun9

1. •
   A navel.
2. •
   A tube connecting an astronaut or spacecraft to the mothership, through which supplies and samples can be transferred.

   • The importance of the visual analyzer is further increased when the cosmonaut is in free space with only the slight support of an umbilicus. — 1966
3. •
   (nonstandard) A umbilical cord.

   • She ate the umbilicus, and the afterbirth, which is supposed to be good for them. Then she licked off the first kitten and was ready for the next. — 1980
4. •
   A hilum.
5. •
   A depression or opening in the center of the base of many spiral shells.
6. •
   Either of the two apertures in the calamus of a feather.
7. •
   A point of a surface at which the curvatures of the normal sections are all equal to each other.

   • A sphere may be osculatory to the surface in every direction at an umbilicus.
8. •
   (historical) An ornamented or painted ball or boss fastened at each end of the stick on which manuscripts were rolled.

   • The ends of the umbilicus were called cornua (i.e. horns) in Latin, and were usually adorned with some pretty device — 1763
9. •
   (no longer used) One of the foci of an ellipse or other curve.