capsaicin

noun

cap·​sa·​i·​cin kap-ˈsā-ə-sən How to pronounce capsaicin (audio)
: a colorless irritant phenolic amide C18H27NO3 found in various capsicums that gives hot peppers their hotness and that is used in topical creams for its analgesic properties

Examples of capsaicin in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
So, this is why, like, capsaicin and chili peppers have this heat sensation because the heat sensing neurons that also respond to capsaicin expressed this one protein. — Quanta Magazine, 6 Aug. 2026 Spicy food ingredients, especially capsaicin—which widens blood vessels and reduces salty food cravings—may be involved if the blood pressure effects of a spicy food diet are scientifically proven. — Colleen Doherty, Verywell Health, 3 Aug. 2026 Chili introduces capsaicin, which activates nerves responsible for sensing heat rather than taste. — Ryan Brennan, Kansas City Star, 30 July 2026 Unlike their spicy relatives, bell peppers contain little to no capsaicin – the compound responsible for a pepper's heat – which gives them their signature crisp texture and mild flavor. — Daryl Austin, USA Today, 29 July 2026 See All Example Sentences for capsaicin

Word History

Etymology

alteration of earlier capsicine, capsicin "material extracted from cayenne pepper," borrowed from German Capsicin, from New Latin Capsicum capsicum + German -in -in entry 1

Note: Name introduced by the British physician and chemist John Clough Thresh (1850-1932) in "Capsaicin, the Active Principle of Capsicum Fruits," The Pharmaceutical Journal and Transactions, 3. series, Vol. 7 (July 3, 1876), p. 21. Thresh altered the name more or less arbitrarily, presumably to prevent confusion with the name for the earlier mixture, the impurity of which he demonstrated. German Capsicin appears to have been introduced by the chemist Christian Friedrich Buchhol(t)z in "Chemische Untersuchung der trockenen reifen spanischen Pfeffers," Almanach oder Taschenbuch für Scheidekünstler und Apotheker, vol. 37 (1816), pp. 1-30.

First Known Use

1876, in the meaning defined above

Time Traveler
The first known use of capsaicin was in 1876

Rhymes for capsaicin

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Browse Nearby Words

caps
capsaicin
capsanthin
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Cite this Entry

“Capsaicin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/capsaicin. Accessed 13 Aug. 2026.

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Medical Definition

capsaicin

noun
cap·​sa·​icin kap-ˈsā-ə-sən How to pronounce capsaicin (audio)
: a colorless irritant phenolic amide C18H27NO3 found in various capsicums that gives hot peppers their hotness and that is used in topical creams for its analgesic properties see zostrix

More from Merriam-Webster on capsaicin

Britannica.com: Encyclopedia article about capsaicin

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