monotocardian
/məˌnəʊtəuˈkɑːdɪən/Zoology
adjective
Designating or relating to prosobranch molluscs having only one gill and whose heart consists of one auricle and one ventricle (formerly placed in a suborder Monotocardia).
noun
A monotocardian gastropod.
Origin
Early 20th century; earliest use found in Quarterly Journal of Microscopical Science. From scientific Latin Monotocardia, former suborder name + -an.