Any cystic lesion associated with the umbilical cord.
Comment:
Umbilical cord cysts can be single or multiple. Most usually, a solitary umbilical cyst is observed. They can be classified as (i) true cysts if they have an epithelial lining (allentoic cyst or omphalomesenteric duct cyst) or false cysts if they do not have an epithelial lining (umbilical cord pseudocyst).