English Reference

Word

hippocampus

Phoneticship·pocam·pus

US/ˌhɪpoʊˈkæmpəs/

UK/hˈɪpəkˌæmpəs/

Definitions

01part of the brain

C1 · Medicine

n. a part of your brain that is very important for memory and learning your way around places.

n. a major component of the brain of humans and other vertebrates, forming part of the limbic system and involved in the formation of new memories.

“Damage to the hippocampus can make it very difficult for a person to form new memories.”

“Neuroscientists have observed that the hippocampus plays a vital role in consolidating information from short-term memory to long-term memory.”

Technical

Usage

Usually used with the definite article 'the' when referring to the specific brain structure.

02mythical creature

C2

n. a creature from old Greek stories that has the head and front legs of a horse and the tail of a fish.

n. a mythological sea monster depicted as having the forequarters of a horse and the hindquarters of a fish or dolphin.

“The ancient fountain was decorated with statues of a hippocampus and other sea creatures.”

“In classical art, the chariot of Poseidon was frequently depicted as being drawn by a pair of powerful hippocampi through the waves.”

Literary

Synonyms

sea-horse

Real-World Examples

“Exercise doesn’t simply boost muscle mass, it bulks up the hippocampus – a key region of the brain involved in learning and memory.”
The Guardian · 9 Aug 2026
“Researchers believe the association between navigation-heavy work and lower Alzheimer’s risk centers on the hippocampus, a part of the brain that governs memory and spatial navigation.”
The Conversation · 6 Aug 2026
“Over time, chronic stress reshapes the hippocampus, a part of the brain where memories get encoded, making learning itself harder .”
The Conversation · 31 Jul 2026
“Slc6a20a is found mainly in brain regions involved in cognition, including the cortex and hippocampus.”
ScienceDaily · 7 Aug 2026

Etymology

From Late Latin hippocampus, from Ancient Greek ἱππόκαμπος (hippókampos, from ῐ̔́ππος (hĭ́ppos, “horse”) + κάμπος (kámpos, “sea-monster”)). The anatomy sense is so named from its resemblance to the seahorse. By surface analysis, hippo- + campus.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Domain

Anatomy

This entry

Level
C1 · Advanced
Frequency
Occasional
Updated

Scan code

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English Reference