eccyesis ec·cye·sis uncommon noun 1. pregnancy resulting from gestation elsewhere than in the uterus Synonymsectopic pregnancyextrauterine pregnancyectopic gestationextrauterine gestationmetacyesis Related words Broader terms pregnancy Narrower terms abdominal pregnancyovarian pregnancytubal pregnancy WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.