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 responsible for many memory functions, and the mice dosed with ayahuasca also performed better in a battery of memory tests. Caroline Delbert, Popular Mechanics, "Ayahuasca Could Do Something Amazing to Your Brain, Study Shows," 10 Nov. 2020 When someone is experiencing emotional stress, the body releases the hormone cortisol, which inhibits normal activity in the hippocampus, the area of the brain where new memories are created. Sara Harrison, Wired, "Confused About Covid Brain Fog? Doctors Have Questions, Too," 6 Nov. 2020 This study tracked cells in the hippocampus, a curved structure near the center of the brain in both species that’s vital for learning and memory. Quanta Magazine, "Brain Cell DNA Refolds Itself to Aid Memory Recall," 2 Nov. 2020 In sea lions, scientists have used brain imaging to document how the toxins also lead to degradation to a part of the brain called the hippocampus that is involved in memory, navigation and other functions. Matt Richtel, New York Times, "Brain Surgery for a ‘Sweet Boy’: Saving Cronutt the Sea Lion," 8 Oct. 2020 Coin depicting a Phoenician ship and a hippocampus. Mark Woolmer, National Geographic, "Purple Reign: A passion for purple built the Phoenicians' vast trading empire," 24 Sep. 2020 These situations foster learned helplessness, negatively impacting the hippocampus, which handles memory functions, and the amygdala, which processes emotions. Bob Jacobs, The Conversation, "The neural cruelty of captivity: Keeping large mammals in zoos and aquariums damages their brains," 24 Sep. 2020 Quietude, though, has been shown to promote the regeneration of brain cells in the hippocampus, which is key for learning, memory and emotion. Pete Mcbride, Smithsonian Magazine, "The Last Quiet Places," 18 Sep. 2020 Scientists trained subjects to exercise control over a single neuron, linked the hippocampus to regret, and concluded that humans smell in stereo. Rafil Kroll-zaidi, Harper's Magazine, "Findings," 18 Aug. 2020

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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Time Traveler for hippocampus

Time Traveler

The first known use of hippocampus was in 1695

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Statistics for hippocampus

Last Updated

22 Nov 2020

Cite this Entry

“Hippocampus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hippocampus. Accessed 24 Nov. 2020.

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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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