eumelanin
noun
eu·mel·a·nin
(ˈ)yü-ˈme-lə-nən 
plural eumelanins
: a brown to black pigment that is the most common form of melanin and whose functions include protecting the epidermis against damage from ultraviolet radiation
Although we can temporarily raise the amount of eumelanin in our skin by tanning, the baseline amount is controlled by our genes.—
Neil Singh
Neil SinghIf eumelanin was the hadrosaur's only pigment, it would have had grey skin like that of a rhinoceros or an elephant.—Michael Marshall
Michael MarshallResearch shows that black hair contains about 99 percent eumelanin, brown and blond hair 95 percent eumelanin, and red hair 67 percent eumelanin.—Kathy Wollard
compare neuromelanin, pheomelanin
Kathy WollardExamples of eumelanin in a Sentence
Recent Examples on the Web
With pheomelanin, the red-brown, red-hair melanins being more jellybean-shaped, and the eumelanin being more hot-dog-shaped.
—Quanta Magazine, 21 Aug. 2025
Through an unknown mechanism, this change may alter pigment production away from dark eumelanin to lighter pheomelanin – orange.
—Grrlscientist, Forbes.com, 2 June 2025
There are two types of hair melanin: pheomelanin, which produces blond and red hair, and eumelanin, which makes darker hair.
—Rj MacKenzie, Popular Science, 20 Mar. 2025
No or very little eumelanin or pheomelanin (albinism) tends to produce pale skin/white hair.
—Heather Jones, Verywell Health, 1 Aug. 2024
This is caused by a natural increase in eumelanin, which determines brown or black pigment, due to hormones.
—Shelby Wax, Allure, 29 Feb. 2024
There are three basic types of the pigment: eumelanin, pheomelanin and neuromelanin.
—Daryl Austin, USA TODAY, 1 Sep. 2023
Their skin adapted to subtle, seasonal changes in sunlight and UV conditions by producing more eumelanin and becoming darker in the summer and then losing some pigment in the fall and winter when the sun wasn’t so strong.
—Nina G. Jablonski, The Conversation, 6 Sep. 2022
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.
Quanta Magazine, 21 Aug. 2025
Through an unknown mechanism, this change may alter pigment production away from dark eumelanin to lighter pheomelanin – orange.
—Grrlscientist, Forbes.com, 2 June 2025
There are two types of hair melanin: pheomelanin, which produces blond and red hair, and eumelanin, which makes darker hair.
—Rj MacKenzie, Popular Science, 20 Mar. 2025
No or very little eumelanin or pheomelanin (albinism) tends to produce pale skin/white hair.
—Heather Jones, Verywell Health, 1 Aug. 2024
This is caused by a natural increase in eumelanin, which determines brown or black pigment, due to hormones.
—Shelby Wax, Allure, 29 Feb. 2024
There are three basic types of the pigment: eumelanin, pheomelanin and neuromelanin.
—Daryl Austin, USA TODAY, 1 Sep. 2023
Their skin adapted to subtle, seasonal changes in sunlight and UV conditions by producing more eumelanin and becoming darker in the summer and then losing some pigment in the fall and winter when the sun wasn’t so strong.
—Nina G. Jablonski, The Conversation, 6 Sep. 2022
Cite this Entry
“Eumelanin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/eumelanin. Accessed 4 Nov. 2025.
Copy CitationMedical Definition
eumelanin
noun
eu·mel·a·nin
(ˈ)yü-ˈme-lə-nən
: a brown to black pigment that is the most common form of melanin
Note: Epidermal eumelanin helps to protect against damage from ultraviolet radiation by scattering and absorbing radiation reducing its penetration through the skin.
The more eumelanin (brown pigment) you have, the darker your skin color …—Scientific American
Scientific AmericanResearch shows that black hair contains about 99 percent eumelanin, brown and blond hair 95 percent eumelanin, and red hair 67 percent eumelanin.—Kathy Wollard, Newsday
Kathy Wollard, NewsdayThe marked spectrum of color and diversity of patterns that we are in mammals arises, unexpectedly, from variation in the quantity, quality, and regional distribution of just two types of pigment—black eumelanin and yellow pheomelanin.—Sophie I. Candille et al., Science
compare neuromelanin, pheomelanin
Sophie I. Candille et al., ScienceLove words? Need even more definitions?
Merriam-Webster unabridged
Share