Congenital malformation in which a hollow organ has its interior exposed through eversion; most commonly observed in the urinary bladder (ectopia vesicae).
Source:
PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 753 (https://doi.org/10.1515/pac-2015-1202)