protrochula

noun

pro·​troch·​u·​la

prō‧ˈträkyələ

plural -s

: a hypothetical free-swimming primitive organism resembling a simple trochophore and regarded as indicating the way of transition from radial to bilateral symmetry

Word History

Etymology

New Latin, from pro- entry 1 + troch- + -ula (feminine of -ulus -ule)

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