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

The hippocampus is primarily responsible for memory and learning, and commonly shrinks, or atrophies, after a stroke. —New Atlas, 6 Sep. 2025

SuperAger brains also have bigger, healthier cells in the entorhinal cortex, an area essential for memory and learning, that has direct connections to the hippocampus. —Sandee Lamotte, CNN Money, 7 Aug. 2025

This result suggests that the infant hippocampus can create memories after only a brief experience. —Nick Turk-Browne, Scientific American, 28 July 2025

The olfactory cortex is closely connected to the amygdala, a part of the brain that processes emotions, and to the hippocampus, a key region for memory. —Margaret Talbot, New Yorker, 10 July 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