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

Recent Examples on the Web

But studies have never proved that depressed people suffer from low serotonin (some do, some have normal levels and others have high levels). Maggie Jones, New York Times, "A Reckoning With an Imperfect Science in ‘Blue Dreams’," 3 Apr. 2018 Progesterone may also influence neurotransmitters like serotonin, which help establish your mood. Zahra Barnes, SELF, "11 Symptoms of Premenstrual Dysphoric Disorder You Shouldn’t Ignore," 6 Feb. 2018 In effect, the drugs increase the concentration of serotonin, another neurotransmitter that fascinated Dr. Carlsson. Harrison Smith, Washington Post, "Arvid Carlsson, Nobel laureate who uncovered a treatment for Parkinson’s, dies at 95," 2 July 2018 These are thought to increase feel-good neurotransmitters like serotonin and dopamine, Stepita says. Stephanie Eckelkamp, Good Housekeeping, "9 Tips For Keeping Your Pet Calm And Safe During Fireworks," 30 June 2017 So the England run has been a kind of serotonin to all of that. Ceylan Yeginsu, New York Times, "World Cup Brings England Together at a Time of Division," 10 July 2018 The rabbits did not improve when given a drug that spurs production of serotonin. Denise Gellene,, "Arvid Carlsson, 95; discovered a treatment for Parkinson’s," 2 July 2018 The researchers, Nirit Soffer-Dudek and Eli Somer, suspect that low levels of serotonin may thus play a role in MD, as is also the case with OCD. Katie Heaney, The Cut, "Excessive Daydreaming Might Be a Form of Mental Illness," 25 June 2018 The receptive neurons, starved of serotonin through the winter months, are now flooded with this neurotransmitter, which is known to be important for mood regulation. NBC News, "This is your brain on spring fever," 13 May 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

6 Oct 2018

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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

What made you want to look up serotonin? Please tell us where you read or heard it (including the quote, if possible).


evasion of direct action or statement

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