serotonin

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

Updated on: 22 Apr 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

Those include drugs that target serotonin receptors and a device that electrically stimulates the phrenic nerve to force diaphragm movement and maintain breathing.

— max blau, STAT, "The next naloxone? Companies, academics search for better overdose-reversal drugs," 10 Apr. 2018
These days, about 5 percent of expectant mothers use antidepressants, most commonly, serotonin reuptake inhibitors, or SSRIs, such as citalopram (brand name Celexa), paroxetine (Paxil), or sertraline (Zoloft).

— julia belluz, Vox, "We’re beginning to learn how moms’ antidepressants can affect fetuses," 9 Apr. 2018
At the same time, Slater notes, few studies have examined the long-term side effects of these serotonin boosters.

— maggie jones, New York Times, "A Reckoning With an Imperfect Science in ‘Blue Dreams’," 3 Apr. 2018
But new lovebirds also experience a spike in the stress hormone cortisol and a concurrent drop in the mood-regulating neurotransmitter serotonin, according to a letter from the Harvard Mahoney Neuroscience Institute.

— jamie ducharme, Time, "5 Ways Love Is Good for Your Health," 14 Feb. 2018
That's the kind of serotonin flood that hit my body.

— darla murray, Cosmopolitan, "10 Guys Reveal the Movie Sex Scene That Turns Them on Most," 16 June 2017
Too little serotonin is associated with depression.

— elizabeth bernstein, WSJ, "The Food That Helps Battle Depression," 2 Apr. 2018
Well, about 95 percent of the body’s serotonin is in the gut, not the brain!

— paul root wolpe, Vox, "A human head transplant would be reckless and ghastly. It’s time to talk about it.," 2 Apr. 2018
The announcer explains that the sudden release of sugar into his body has triggered a release of serotonin, which has caused his body to shut down.

— steve helling, PEOPLE.com, "Naked and Afraid Survivalist Goes Into a Food Coma After Starving for 12 Days," 1 Apr. 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