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

London taxi drivers, who have to memorize all possible routes across tens of thousands of roads to earn their license, have a larger and more developed posterior hippocampus relative to London bus drivers, who simply follow pre-set routes. —Celia Ford, Vox, 10 Mar. 2025

In the original visual, the Grammy winner plays a heartbroken character named Peaches who has all traces of her ex wiped from her hippocampus, an homage to Michel Gondry’s 2004 film Eternal Sunshine of the Spotless Mind. —Hannah Dailey, Billboard, 26 Mar. 2025

Researchers long thought that the hippocampus, the region of the brain that’s in charge of making memories, wasn’t developed enough during infancy to encode specific events as memories. —Sam Walters, Discover Magazine, 20 Mar. 2025

From the hippocampus, a crucial memory hub, to the vast neural networks in our cortex, the brain continuously forms new connections. —Talia Milgrom-Elcott, Forbes, 13 Mar. 2025

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