1
: a product of living cells that circulates in body fluids (such as blood) or sap and produces a specific often stimulatory effect on the activity of cells usually remote from its point of origin
also : a synthetic substance that acts like a hormone
2

Examples of hormone 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.
That could result in unexpected and negative reactions from your body such as inflammation and disruption of your hormones. Bruce Y. Lee, Forbes.com, 10 July 2026 These chronotypes likely come from complex interactions between people’s genetics, hormone fluctuations and environment, which includes aspects such as their work schedules or light exposure. Kate Graham-Shaw, Scientific American, 9 July 2026 For instance, the researchers didn’t measure appetite hormones, brain activity, or other body signals that could explain the mechanisms in play. Emily Kay Votruba, EverydayHealth.com, 9 July 2026 Researchers found that increasing protein intake reduces ghrelin levels, a hunger hormone. Mark Gurarie, Verywell Health, 7 July 2026 See All Example Sentences for hormone

Word History

Etymology

Greek hormōn, present participle of horman to stir up, from hormē impulse, assault; akin to Greek ornynai to rouse — more at rise

First Known Use

1905, in the meaning defined at sense 1

Time Traveler
The first known use of hormone was in 1905

Browse Nearby Words

Cite this Entry

“Hormone.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hormone. Accessed 12 Jul. 2026.

Kids Definition

: a product of living cells that circulates in body fluids (as blood) or sap and produces a specific and often stimulating effect on cells usually at a distance from the place where it is made

Medical Definition

1
a
: a product of living cells that circulates in body fluids (as blood) or sap and produces a specific often stimulatory effect on the activity of cells usually a distance from its point of synthesis
Some people develop insulin resistance, a condition in which response to the hormone is muted and the body must produce excess insulin to maintain healthy blood-glucose concentrations.Ben Harder, Science News
b
: a synthetic substance that acts like a hormone
2
: sex hormone
I discovered I had the classic signs of perimenopause, the prelude to "the change" when hormones yo-yo before menstrual periods cease altogether …Beth Witrogen McLeod, Cooking Light

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