protocephalon

noun

pro·​to·​cephalon

¦prōt(ˌ)ō+

plural protocephala

1

: the part of an insect embryo that consists of the prostomium and the first postoral somite

2

: the primitive arthropod head corresponding to the sensory as distinguished from the feeding portion of the head of higher forms compare gnathothorax

Word History

Etymology

New Latin, from prot- + cephalon

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