hippocampus
Concise Oxford English Dictionary © 2008 Oxford University Press:
hippocampus /ˌhɪpə(ʊ)ˈkampəs/
▶noun (pl. hippocampi /-pi, -pʌɪ/) Anatomy the system of elongated ridges on the floor of the lateral ventricles of the brain, thought to be the centre of emotion, memory, and the autonomic nervous system.
– origin C16: via L. from Gk hippokampos, from hippos ‘horse’ + kampos ‘sea monster’.
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