- a navel-like depression, as the hilum of a seed
Origin of umbilicusL, navel
- See navel.
- Biology A small opening or depression similar to a navel, as the hollow at the base of the shell of some gastropod mollusks, one of the openings in the shaft of a feather, or the hilum of a seed.
Origin of umbilicusLatin umbil&imacron;cus; see nobh- in Indo-European roots.
(plural umbilici or umbilicuses)
- (anatomy) navel
- (botany) hilum
- (zoology) A depression or opening in the center of the base of many spiral shells.
- (zoology) Either of the two apertures in the calamus of a feather.
- (geometry) 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.
- (historical) An ornamented or painted ball or boss fastened at each end of the stick on which manuscripts were rolled.
From Latin umbilÄ«cus (“navel").