hippocampus

noun

hip·​po·​cam·​pus ˌhi-pə-ˈkam-pəs 

plural hippocampi ˌhi-pə-ˈkam-ˌpī  -(ˌ)pē 

: a curved elongated ridge that extends over the floor of the descending horn of each lateral ventricle of the brain, that consists of gray matter covered on the ventricular surface with white matter, and that is involved in forming, storing, and processing memory

hippocampal

ˌhi-pə-ˈkam-pəl 

adjective

Examples of hippocampus in a Sentence

Recent Examples on the Web

Two of the main brain structures scientists believe are involved in storing traumatic memories are the hippocampus—responsible for memory storage—and the amygdala, which is responsible for processing emotions. — Michele Patterson Ford, Scientific American, 22 Aug. 2026

Synaptic purge To find out how many synapses are lost during QIH, Tanaka’s team implanted tetrodes, bundles of fine electrodes, into the hippocampus of freely moving mice. — Jacek Krywko, ArsTechnica, 22 Aug. 2026

People on antidepressants saw activity boosts in their left hippocampus, which is involved in memory and stress regulation, along with the right middle occipital gyrus, which is a visual processing area. — Korin Miller, Allure, 21 Aug. 2026

Two of the main brain structures scientists believe are involved in storing traumatic memories are the hippocampus – responsible for memory storage – and the amygdala, which is responsible for processing emotions. — Michele Patterson Ford, The Conversation, 19 Aug. 2026

Word History

Etymology

New Latin, from Greek hippokampos seahorse, from hippos horse + kampos sea monster — more at equine

First Known Use

1695, in the meaning defined above

Rhymes for hippocampus

• campus
• grampus

Medical Definition

hippocampus

noun

hip·​po·​cam·​pus ˌhip-ə-ˈkam-pəs 

plural hippocampi -ˌpī  -(ˌ)pē 

: a curved elongated ridge that is an important part of the limbic system, extends over the floor of the descending horn of each lateral ventricle of the brain, consists of gray matter covered on the ventricular surface with white matter, and is involved in forming, storing, and processing memory see pes hippocampi