se·​ro·​to·​nin | \ ˌsir-ə-ˈtō-nən, ˌser-\

Definition of serotonin 

: a phenolic amine neurotransmitter C10H12N2O that is a powerful vasoconstrictor and is found especially in the brain, blood serum, and gastric mucous membrane of mammals

Examples of serotonin in a Sentence

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These work by obstructing how easily your brain reabsorbs serotonin, a neurotransmitter that can affect your mood, the Mayo Clinic explains. Cassie Shortsleeve, SELF, "Is There a Difference Between an Anxiety Attack and a Panic Attack?," 12 Sep. 2018 In addition to dopamine, atypical antipsychotics can also affect levels of mood-affecting neurotransmitters like serotonin, norepinephrine, and others, Dr. Li explains. Carolyn L. Todd, SELF, "9 Things You Should Know About Taking Antipsychotic Drugs," 7 Dec. 2018 This amino acid triggers the release of serotonin, which is a feel-good brain chemical. Marie Claire, "9 Foods That Reduce Stress Levels," 21 Mar. 2010 Antipsychotics generally work by affecting the levels of brain neurotransmitters that impact mood, like serotonin and dopamine, Dr. Alan explains. Korin Miller, SELF, "5 Bipolar Disorder Treatments You Should Know About," 30 Nov. 2018 One species has been found to enhance serotonin production, which can lead to greater happiness and lower stress. Lisa Margonelli, WSJ, "‘Never Home Alone’ Review: The Critters Chez Nous," 28 Nov. 2018 This drug belongs to a group of popular migraine medications called triptans, which increase the amount of serotonin in your brain, helping your blood vessels to constrict and reducing pain, according to the NINDS. Korin Miller, SELF, "Neurologists Share Exactly How They Deal With Their Migraines," 1 Aug. 2018 Vitamin B6: An ingredient needed to produce serotonin, the main neurotransmitter that regulates mood and sleep. Elizabeth Bernstein, WSJ, "The Food That Helps Battle Depression," 2 Apr. 2018 By the 1950s, scientists studying LSD had discovered serotonin, figured out that the human brain was full of something called neurotransmitters and begun inching toward the development of the first antidepressants. Tom Bissell, New York Times, "Michael Pollan Drops Acid — and Comes Back From His Trip Convinced," 4 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'serotonin.' 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 serotonin

1948, in the meaning defined above

History and Etymology for serotonin

sero- + tonic + -in entry 1

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Last Updated

13 Jan 2019

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Time Traveler for serotonin

The first known use of serotonin was in 1948

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se·​ro·​to·​nin | \ ˌsir-ə-ˈtō-nən, ˌser- \

Medical Definition of serotonin 

: a phenolic amine neurotransmitter C10H12N2O that is a powerful vasoconstrictor and is found especially in the brain, blood serum, and gastric mucous membrane of mammals

called also 5-HT, 5-hydroxytryptamine

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More from Merriam-Webster on serotonin

Nglish: Translation of serotonin for Spanish Speakers

Britannica English: Translation of serotonin for Arabic Speakers Encyclopedia article about serotonin

Comments on serotonin

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a person who helps groups work together

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