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

When your body recognizes a strong emotion tied to a food smell, the emotional center of your brain – the amygdala – alerts the part of your brain that forms and stores long-term memories, your hippocampus. —Bryn Beeder, The Conversation, 17 Nov. 2025

Rats are able to build cognitive maps in their hippocampus, and then update them only when something important changes. —Christopher McFadden, Interesting Engineering, 15 Nov. 2025

The hippocampus is also implicated in a number of mental activities beyond cognitive maps. —Literary Hub, 14 Nov. 2025

Stress can lead to shrinkage in specific areas of the brain, such as the hippocampus, while also causing negative changes in the prefrontal cortex and the amygdala. —Angelica Bottaro, Verywell Health, 6 Nov. 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