The Collaborative International Dictionary
Cephalosome
Cephalosome \Ceph"a*lo*some\ (s[e^]f"[.a]*l[-o]*s[=o]m, n.
[Cephalo- + -some body.] (Zo["o]l.)
The anterior region or head of insects and other arthropods.
--Packard.
Wiktionary
cephalosome
n. (context zoology English) The anterior region or head of insects and other arthropods.