- hippocampus - a complex neural structure (shaped like a sea horse) consisting of gray matter and located on the floor of each lateral ventricle; intimately involved in motivation and emotion as part of the limbic system; has a central role in the formation of memories
--1 is a kind of neural structure
--1 is a part of limbic system, visceral brain, limbic brain- Hippocampus, genus Hippocampus - seahorses
--2 is a kind of fish genus
--2 is a member of Syngnathidae, family Syngnathidae
--2 has members: seahorse, sea horse - Hippocampus, genus Hippocampus - seahorses