The remnant of an omphalomesenteric duct is
The omphalomesenteric duct is an embryonic structure which connects the yolk sac to the midgut, it gets obliterated between the 5thand 9th week of gestation, failure of which result in remnants like Meckel's diveiculum or cyst or fistula The median umbilical ligament is a remnant of the urachus The medial umbilical ligaments are a remnant of the umbilical aeries Ref: Gray's 39e/p-1289
Median umbilical ligament
Meckel's diveiculum
Median umbilical fold
Omphalocele
General anatomy