plural protocephala
: the part of an insect embryo that consists of the prostomium and the first postoral somite
: the primitive arthropod head corresponding to the sensory as distinguished from the feeding portion of the head of higher forms compare gnathothorax

Word History


New Latin, from prot- + cephalon

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Dictionary Entries Near protocephalon

Cite this Entry

“Protocephalon.” Dictionary, Merriam-Webster, Accessed 19 Apr. 2024.

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