serotonin

noun

se·​ro·​to·​nin ˌsir-ə-ˈtō-nən 

ˌser-

: 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

There’s also evidence that estrogen influences key neurotransmitters like serotonin and dopamine (which help regulate things like mood, motivation, and body functions), as well as improves connectivity between brain regions, Dr. Rosenbloom adds. —Carolyn L. Todd, SELF, 12 May 2025

This may be due to its ability to restore the activity of neurotransmitters, such as serotonin and dopamine, which are chemical messengers in the brain.11 Animal studies show curcumin can reduce symptoms of depression, and some clinical trials support these findings. —Lauren O'Connor, Health, 5 May 2025

Unexpected ingredients: Some supplements include serotonin (a mood-regulating chemical) that can be harmful in high amounts. —Jonathan B. Jassey, Verywell Health, 5 May 2025

Mood swings are common due to fluctuating estrogen levels affecting serotonin and dopamine. —Jess Cording, Forbes.com, 21 Apr. 2025

Word History

Etymology

sero- + ton(ic) entry 2 or tone entry 1 + -in entry 1, probably after angiotonin, earlier name for angiotensin — more at angiotensin

Note: Term introduced by Maurice M. Rapport, Arda Alden Green and Irvine H. Page in "Crystalline serotonin," Science, vol. 108, Issue 2804 (September 24, 1948), pp. 329-330: "The general behavior of the crystalline substance is suggestive of its homogeneity. We would like provisionally to name it serotonin, which indicates that its source is serum and its activity is one of causing constriction."

First Known Use

1948, in the meaning defined above

Phrases Containing serotonin

• selective serotonin reuptake inhibitor

Rhymes for serotonin

• calcitonin
• digitonin
• melatonin
• kronen
• onan
• phonon
• ronin
• santonin

Medical Definition

serotonin

noun

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

: 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