capsaicin

American  

[kap-sey-uh-sin] / kæpˈseɪ ə sɪn /

noun

1. a colorless, crystalline, bitter compound, C 18 H 27 NO 3 , present in capsicum.

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capsaicin British  

/ kæpˈseɪɪsɪn /

noun

1. a colourless crystalline bitter alkaloid found in capsicums and used as a flavouring in vinegar and pickles. Formula: C 18 H 27 O 3 N

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capsaicin Scientific  

/ kăp-sā′ĭ-sĭn /

1. A colorless, extremely pungent, crystalline compound that is the primary active principle producing the heat of red peppers. It is a strong irritant to skin and mucous membranes and is used in medicine as a topical analgesic. Capsaicin is highly stable, retaining its potency for long periods and despite cooking or freezing. Chemical formula: C ₁₈ H ₂₇ NO ₃ .

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Etymology

Origin of capsaicin

1885–90; earlier capsicine, equivalent to capsic(um) + -ine ²; refashioned with capsa- (< Latin: box) for caps- and -in ² for -ine ²

Example Sentences

The substance is believed to have been an irritant spray, identified by authorities as likely containing capsaicin - which is found in chilli peppers.

From BBC • May 25, 2026

When tested individually, capsaicin showed the strongest anti-inflammatory effect.

From Science Daily • Apr. 9, 2026

But researchers also note that targeted capsaicin delivery may help defend against other conditions brought on or exacerbated by oxidative damage, including many cancers.

From Science Magazine • Mar. 29, 2024

I read that capsaicin could be helpful, so I bought Sloan’s Liniment.

From Seattle Times • Feb. 14, 2024

The chief constituents are a crystallizable resin, capsaicin, a volatile alkaloid, capsicine and a volatile oil.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 5 "Cat" to "Celt" by Various