Definitions for urachus
a cord or band of fibrous tissue extending from the bladder to the umbilicus
U.S. National Library of Medicine
An embryonic structure originating from the ALLANTOIS. It is a canal connecting the fetal URINARY BLADDER and the UMBILICUS. It is normally converted into a fibrous cord postnatally. When the canal fails to be filled and remains open (patent urachus), urine leaks through the umbilicus.