hip·​po·​cam·​pus | \ ˌhi-pə-ˈkam-pəs How to pronounce hippocampus (audio) \
plural hippocampi\ ˌhi-​pə-​ˈkam-​ˌpī How to pronounce hippocampi (audio) , -​(ˌ)pē \

Definition of hippocampus

: 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

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Other Words from hippocampus

hippocampal \ ˌhi-​pə-​ˈkam-​pəl How to pronounce hippocampal (audio) \ adjective

Examples of hippocampus in a Sentence

Recent Examples on the Web

The hippocampus is the region where these egocentric, episodic memories are made. Diana Gitig, Ars Technica, "Collating memories of what happened based on where it happened," 25 Nov. 2018 Knowing how to do something does not require the hippocampus. Susan Pinker, WSJ, "An Unforgettable Memory Expert Muses at 100," 23 Aug. 2018 Connections between the amygdala and hippocampus were also weak in the infected macaques, which suggests signals sent between those two areas—ones that would help the infants recognize and respond to stressful situations—would be slow or spotty. Dina Fine Maron, Scientific American, "Zika Exposure Even after Birth May Lead to Brain Damage," 4 Apr. 2018 The imaging scan showed that her hippocampus, the brain region that regulates memory, had severely atrophied and was in the 14th percentile for her age — 86 percent of peers were better off. Linda Marsa, Discover Magazine, "A New Treatment for Alzheimer's? It Starts With Lifestyle," 16 Nov. 2018 Many structures that are important for memory encoding and retrieval, such as the hippocampus, lie outside the cortex—and Lashley largely missed them. Helen Shen, Scientific American, "Portrait of a Memory," 14 Mar. 2018 All the while, electrodes were recording the brain’s activity, tracking the firing patterns in the hippocampus when the patient guessed right and wrong. Robbie Gonzalez, WIRED, "A Brain-Boosting Prosthesis Moves From Rats to Humans," 6 Apr. 2018 The hippocampus, a curved structure shaped like the seahorse it is named after, plays a role in learning and memory. Darby Saxbe, Scientific American, "Living with Neighborhood Violence May Shape Teens’ Brains," 15 June 2018 And without it, the parts of the brain that deal with attachment and fear — the amygdala and hippocampus — develop differently. William Wan, Washington Post, "What separation from parents does to children: ‘The effect is catastrophic’," 18 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hippocampus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of hippocampus

1695, in the meaning defined above

History and Etymology for hippocampus

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

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Statistics for hippocampus

Last Updated

14 Mar 2019

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Time Traveler for hippocampus

The first known use of hippocampus was in 1695

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More Definitions for hippocampus


hip·​po·​cam·​pus | \ ˌhip-ə-ˈkam-pəs How to pronounce hippocampus (audio) \
plural hippocampi\ -​ˌpī How to pronounce hippocampi (audio) , -​(ˌ)pē How to pronounce hippocampi (audio) \

Medical Definition of hippocampus

: 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

More from Merriam-Webster on hippocampus

Nglish: Translation of hippocampus for Spanish Speakers

Britannica.com: Encyclopedia article about hippocampus

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