serotonin

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

|Updated on: 11 Aug 2018

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

Recent Examples of serotonin from the Web

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, BostonGlobe.com, "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
SSRIs work by blocking the reabsorption (reuptake) of serotonin in the brain, according to the Mayo Clinic.

— martine thompson, SELF, "8 Things You Should Know Before Going on Antidepressants for the First Time," 30 Mar. 2018
During this week, the imbalance of estrogen and progesterone can affect your levels of serotonin and bring on strong premenstrual-syndrome symptoms.

— sarah jio, Woman's Day, "A Month in the Life of Your Hormones," 27 May 2010
Addyi, on the other hand, targets neurotransmitters in the brain like serotonin and dopamine.

— amanda macmillan, Health.com, "The Controversial 'Female Viagra' Drug Is Back–Here's What You Need to Know," 14 June 2018
Biologically speaking, that light tricks the optic nerve into thinking it’s still time to be awake instead of allowing the natural release of melatonin and serotonin in the body to signal the end of the waking day.

— katie parsons, OrlandoSentinel.com, "Americans aren't sleeping enough, but early risers might live longer," 31 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.

Origin and Etymology of serotonin

sero- + tonic + ¹-in

NEW! Time Traveler

First Known Use: 1948

in the meaning defined above

See Words from the same year

Medical Dictionary

serotonin

noun 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