Definitionen
1.NounAny of the headshield slugs of genus Bulla, belonging to the order Cephalaspidea of gastropods.
A marine univalve shell of the genus Bulla (Bullidae) and certain shells of similar appearance of the now disused order Tectibranchiata of molluscs.
2.NounA marine univalve shell of the genus Bulla (Bullidae) and certain shells of similar appearance of the now disused order Tectibranchiata of molluscs.
3.NounAny of the family Epitoniidae (syn. Janthinidae), of pelagic sea snails.