noun see: stomach Date: 1959 any of a major group (Protostomia) of bilateral metazoan animals (as mollusks, annelids, and arthropods) characterized in typical forms by determinate and spiral cleavage, formation of a mouth and anus directly from the blastopore, and formation of the coelom by splitting of the embryonic mesoderm
PROTOSTOME
Meaning of PROTOSTOME in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012