Umbilical hernia abnormal umbilical cord morphology umbilical hernia Fyler:4445 2010-05-10T02:40:34Z MP:0010146 csmith MPheno.ontology an outward bulging (protrusion) of the abdominal lining or part of the abdominal organ(s) through the area around the umbilicus; occurs when the muscle through which blood vessels pass to feed the developing fetus fails to completely close Do not confuse with omphalocele - a severe body wall defect that results in an abnormally large umbilical ring usually exposing the gut and liver. herniated umbilical cord