1. Biology a hollow or navel-like structure, such as the cavity at the base of a gastropod shell
a technical name for the navel
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.
(also navel), the cicatrix formed in a newborn infant after the remaining part of the umbilical cord has fallen off (fifth to seventh day after birth). If the tissues surrounding the umbilicus (umbilical ring) are not sufficiently sturdy, an umbilical hernia may develop.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
The navel; the round, depressed cicatrix in the median line of the abdomen, marking the site of the aperture through which passed the fetal umbilical vessels.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.