melanin

noun

mel·​a·​nin ˈme-lə-nən How to pronounce melanin (audio)
plural melanins
: any of various black, brown, reddish-brown, reddish-yellow, or yellow pigments of living organisms that in animals are typically produced in melanocytes by the oxidation of tyrosine followed by polymerization and are found especially in skin, hair, feathers, and eyes
Scientists know that all melanin molecules consist of long chains made mostly of derivatives of the amino acid tyrosine, but the individual units of the chain connect in random order.Corinna Wu
Melanin performs an array of functions for modern organisms, such as camouflage, photo protection, and display.Margaret Jones
especially : eumelanin
Tyrosinase enzymes are needed for the manufacture of melanin, the dark pigment that forms the color base of feathers. Philip C. Whitford
Brown spots and birthmarks contain especially high concentrations of melanin, the substance that gives skin its color. USA Today
see also neuromelanin, pheomelanin

Examples of melanin 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.
In that case, your body might overreact and pump out lots of (and sometimes too much) protective melanin. Jenna Ryu, SELF, 18 Oct. 2024 Excessive melanin causes hyperpigmentation in aged skin. New Atlas, 6 Sep. 2024 Research has shown that dark skin pigmentation can impact pulse oximetry results since melanin absorbs more light, preventing the light from penetrating tissue to produce accurate readings. Frank Chan, Forbes, 5 Sep. 2024 The laser emits a beam of light absorbed by the hair pigment (melanin). Iman Balagam, Vogue, 22 Oct. 2024 See all Example Sentences for melanin 

Word History

Etymology

Greek melan-, stem of mélās "black, dark" + -in entry 1, after Italian melaina — more at melano-

Note: The term melaina was introduced in a study of squid ink by the Italian chemist Bartolomeo Bizio (1791-1862), "Ricerche chimiche sovra l'inchiostro della Seppia," Giornale di fisica, chimica, storia naturale, medicina ed arte, decade 2, tomo 8 (1825), p. 105. Bizio formed the word from Greek mélās "black" and aeí "always" because the substance he had isolated retained its color no matter what acid or other potent chemical it was exposed to ("Questo principio animal particolarissimo il fu chiamato così dal greco mélas, nero, ed aeì sempre, che vale materia sempre nera, conciossachè gli acidi, il cloro, e tutto che vi è di più potente, non bastano a mutarlo di colore.")

First Known Use

1843, in the meaning defined above

Time Traveler
The first known use of melanin was in 1843

Dictionary Entries Near melanin

Cite this Entry

“Melanin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/melanin. Accessed 1 Dec. 2024.

Kids Definition

melanin

noun
mel·​a·​nin ˈmel-ə-nən How to pronounce melanin (audio)
: a usually dark brown or black pigment that gives color to skin, hair, feathers, and eyes
Etymology

derived from Greek melan-, melas "black" — related to melancholy

Medical Definition

melanin

noun
mel·​a·​nin ˈmel-ə-nən How to pronounce melanin (audio)
: any of various black, brown, reddish-brown, reddish-yellow, or yellow pigments of living organisms that in animals are typically produced in melanocytes by the oxidation of tyrosine followed by polymerization and are found especially in skin, hair, feathers, and eyes
Scientists know that all melanin molecules consist of long chains made mostly of derivatives of the amino acid tyrosine, but the individual units of the chain connect in random order.Corinna Wu, Science News
especially : eumelanin
Brown spots and birthmarks contain especially high concentrations of melanin, the substance that gives skin its color. USA Today
Natural melanin surrounds and protects our cells not only by absorbing ultraviolet radiation, but also by scattering it and making it lose energy, rendering it harmless. Rowann Gilman, Prevention
see also neuromelanin, pheomelanin

More from Merriam-Webster on melanin

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