leucism

noun

leu·​cism ˈlü-ˌsi-zəm How to pronounce leucism (audio)
: an abnormal condition of reduced pigmentation affecting various animals (such as birds, mammals, and reptiles) that is marked by overall pale color or patches of reduced coloring and is caused by a genetic mutation which inhibits melanin and other pigments from being deposited in feathers, hair, or skin
leucistic adjective

Examples of leucism 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.
The orca's pale complexion may be due to leucism or Chediak-Higashi Syndrome. Fernando Cervantes Jr., USA TODAY, 5 Dec. 2024 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 On social media, some commenters speculated the creature might be a young red or gray fox with leucism, a condition that causes a loss of pigmentation, resulting in white fur. Alexa Robles-Gil, Smithsonian Magazine, 17 Oct. 2024 An animal with leucism experiences a partial loss of pigmentation. Samuel Sanders, Smithsonian Magazine, 12 Sep. 2024 See all Example Sentences for leucism 

Word History

Etymology

borrowed from German Leucismus, from Greek leukós "clear, white" + German -ismus -ism — more at light entry 1

First Known Use

1878, in the meaning defined above

Time Traveler
The first known use of leucism was in 1878

Dictionary Entries Near leucism

Cite this Entry

“Leucism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/leucism. Accessed 21 Dec. 2024.

Last Updated: - Updated example sentences
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