melanism

noun

mel·​a·​nism ˈme-lə-ˌni-zəm 

1

: an increased amount of black or nearly black pigmentation (as of skin, feathers, or hair) of an individual or kind of organism compare industrial melanism

2

: intense human pigmentation of the skin, eyes, and hair

melanistic

ˌme-lə-ˈni-stik 

adjective

Examples of melanism in a Sentence

Recent Examples on the Web

This discrepancy surprised us because the genetic mutation that causes melanism occurs less frequently than the one that causes albinism/leucism. —Elizabeth Carlen, Discover Magazine, 31 Oct. 2024

As pollution levels declined due to regulation, the melanism in these creatures reversed. —Smithsonian Magazine, Smithsonian Magazine, 29 Mar. 2023

With the black variety, a form of melanism increases the dark pigment in their fur. —Brielle Fischman, Discover Magazine, 9 Feb. 2021

To determine the origins of squirrel melanism, or dark coloration, McRobie and colleagues from Cambridge University and the Virginia Museum of Natural History extracted DNA from gray and fox squirrel specimens found in North America. —Meilan Solly, Smithsonian, 16 Aug. 2019

But why melanism evolved in cats is a trickier question. —Sergio Pitamitz, National Geographic, 22 Mar. 2017

The animal is melanistic—its genes carry a mutation that creates more dark pigment than light pigment, according to Eduardo Eizirik, a biologist and cat-melanism expert at Pontifical Catholic University of Rio Grande do Sul in Brazil. —Sergio Pitamitz, National Geographic, 22 Mar. 2017

Word History

Etymology

borrowed from French mélanisme, from Greek melan-, stem of mélās "black, dark" + French -isme -ism, on the model of albinisme albinism — more at melano-

Note: French mélanisme appears in the 1820's, perhaps earliest in De l'organisation des animaux, ou Principes d'anatomie comparée, tome premier (Paris, 1822), by the zoologist Henri Marie Ducrotay de Blainville (1777-1850).

First Known Use

1843, in the meaning defined at sense 1

Phrases Containing melanism

• industrial melanism

Kids Definition

melanism

noun

mel·​a·​nism ˈmel-ə-ˌniz-əm 

: an exceptionally dark coloring (as of skin, feathers, or hair) of an individual or kind of living thing

Medical Definition

melanism

noun

mel·​a·​nism ˈmel-ə-ˌniz-əm 

1

: an increased amount of black or nearly black pigmentation (as of skin, feathers, or hair) of an individual or kind of organism

2

: intense human pigmentation in skin, eyes, and hair

melanistic

ˌmel-ə-ˈnis-tik 

adjective