histamine

noun

his·​ta·​mine ˈhi-stə-ˌmēn How to pronounce histamine (audio) -mən How to pronounce histamine (audio)
: a compound C5H9N3 especially of mammalian tissues that causes dilation of capillaries, contraction of smooth muscle, and stimulation of gastric acid secretion, that is released during allergic reactions, and that is formed by decarboxylation of histidine

Examples of histamine 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.
Because itching is often triggered by histamine (a chemical in the body associated with immune responses), dermatologists had reason to think that antihistamines could effectively subdue the itching caused by eczema. — Rob Williams, EverydayHealth.com, 30 July 2026 Additionally, doctors often recommend over-the-counter antihistamines such as Benadryl to counteract histamine released by the immune system. — Maggie O'Neill, Verywell Health, 29 July 2026 The recall may be particularly relevant to women in midlife, when fluctuating estrogen levels can influence histamine activity and potentially intensify allergy symptoms. — Emily Cegielski, Flow Space, 22 July 2026 The theory is that this combination may help keep histamine in check, basically replacing the effect of progesterone. — Theara Coleman, TheWeek, 1 July 2026 See All Example Sentences for histamine

Word History

Etymology

International Scientific Vocabulary hist- + amine

First Known Use

circa 1913, in the meaning defined above

Time Traveler
The first known use of histamine was circa 1913

Rhymes for histamine

See All Rhymes for histamine

Browse Nearby Words

histaminase
histamine
histamine flare
See all Nearby Words

Cite this Entry

“Histamine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/histamine. Accessed 8 Aug. 2026.

Copy Citation

Kids Definition

histamine

noun
his·​ta·​mine ˈhis-tə-ˌmēn How to pronounce histamine (audio)
-mən
: a compound that occurs in many animal tissues and plays an important part in allergic reactions (as in hives, asthma, and hay fever)

Medical Definition

histamine

noun
his·​ta·​mine ˈhis-tə-ˌmēn How to pronounce histamine (audio) -mən How to pronounce histamine (audio)
: a compound C5H9N3 especially of mammalian tissues that causes dilatation of capillaries, contraction of smooth muscle, and stimulation of gastric acid secretion, that is released during allergic reactions, and that is formed by decarboxylation of histidine
histaminic
ˌhis-tə-ˈmin-ik How to pronounce histamine (audio)
adjective

More from Merriam-Webster on histamine

Britannica.com: Encyclopedia article about histamine

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of nurture

See Definitions and Examples »

Popular in Grammar & Usage

See More

7 Pairs of Commonly Confused Words

Merriam-Webster’s Great Big List of Words You Love to Hate

Is it 'nerve-racking' or 'nerve-wracking'?

'Sneaked' or 'Snuck': Which is correct?

Why does English have so many silent letters?
See More

Popular in Wordplay

See More

The Longest Long Words List

It's a Scorcher! Words for the Summer Heat

14 Phobias You Probably Haven't Heard Of

The Words of the Week - Aug. 7

How long is a jiffy?
See More

Popular

See More

7 Pairs of Commonly Confused Words

The Longest Long Words List

It's a Scorcher! Words for the Summer Heat
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
fridge-magnet-letters
Drop a Letter Quiz August 2026 Drop a letter from a word to make a totally diffe...
See All