evo·lu·tion | \ˌe-və-ˈlü-shən, ˌē-və-\

Definition of evolution 

1a : descent with modification from preexisting species : cumulative inherited change in a population of organisms through time leading to the appearance of new forms : the process by which new species or populations of living things develop from preexisting forms through successive generations Evolution is a process of continuous branching and diversification from common trunks. This pattern of irreversible separation gives life's history its basic directionality.— Stephen Jay Gould also : the scientific theory explaining the appearance of new species and varieties through the action of various biological mechanisms (such as natural selection, genetic mutation or drift, and hybridization) Since 1950, developments in molecular biology have had a growing influence on the theory of evolution. Nature In Darwinian evolution, the basic mechanism is genetic mutation, followed by selection of the organisms most likely to survive. — Pamela Weintraub

b : the historical development of a biological group (such as a race or species) : phylogeny

2a : a process of change in a certain direction : unfolding

b : the action or an instance of forming and giving something off : emission

c(1) : a process of continuous change from a lower, simpler, or worse to a higher, more complex, or better state : growth

(2) : a process of gradual and relatively peaceful social, political, and economic advance

d : something evolved

3 : the process of working out or developing

4 : the extraction of a mathematical root

5 : a process in which the whole universe is a progression of interrelated phenomena

6 : one of a set of prescribed movements

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Other Words from evolution

evolutionarily \ˌe-və-ˈlü-shə-ˌner-ə-lē, ˌē-və- \ adverb
evolutionary \ˌe-və-ˈlü-shə-ˌner-ē, ˌē-və- \ adjective
evolutionism \ˌe-və-ˈlü-shə-ˌni-zəm, ˌē-və- \ noun
evolutionist \ˌe-və-ˈlü-sh(ə-)nist, ˌē-və- \ noun or adjective

Examples of evolution in a Sentence

changes brought about by evolution an important step in the evolution of computers

Recent Examples on the Web

The museum’s single exhibit on human evolution is situated on the top floor, allowing any visitors who may find the subject objectionable for religious reasons to easily bypass it. Washington Post, "AP PHOTOS: Long-dead critters animate Israel’s nature museum," 11 June 2018 The museum's single exhibit on human evolution is situated on the top floor, allowing any visitors who may find the subject objectionable for religious reasons to easily bypass it. Oded Balilty, Fox News, "AP PHOTOS: Long-dead critters animate Israel's nature museum," 11 June 2018 Though a famous study from 1980 argued that based on the evolution of human jaws and teeth, our ancient ancestors used to eat a diet dominated by fruit, there’s not a lot of good evidence for or against fruit-heavy diets for modern humans. Markham Heid, Time, "Is It Possible To Eat Too Much Fruit?," 6 June 2018 Painted on the walls are lessons on the evolution of Chemex brewing and the siphon pot. Mike Sutter, San Antonio Express-News, "Top 5 coffee shops in San Antonio," 4 June 2018 Keep your eye on the evolution of the photographer’s name, for that is the story of Weegee. Sarah Boxer, New York Times, "Weegee the Famous: The Master of Down-and-Dirty Street Photography," 1 June 2018 Kipling did not ignore people in his quirky take on evolution. The Economist, "A history of big-headedness," 31 May 2018 This was a statement on the evolution of America’s relationship with race, as told through the story of the Walt Disney Co. Solomon Jones, Philly.com, "With black women in power, Roseanne's show never stood a chance. Thank God | Solomon Jones," 29 May 2018 Ashley Hammond, an expert on the evolution of locomotion in great apes and early humans, will take up the post on June 1. Michael Balter, Scientific American, "Leading Science Museum Turns the Page on a Prominent #MeToo Case," 21 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'evolution.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of evolution

1616, in the meaning defined at sense 6

History and Etymology for evolution

Latin evolution-, evolutio unrolling, from evolvere

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Last Updated

27 Sep 2018

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The first known use of evolution was in 1616

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More Definitions for evolution


evo·lu·tion | \ˌe-və-ˈlü-shən, ˌē-və-\

Kids Definition of evolution

1 : the theory that the various kinds of existing animals and plants have come from kinds that existed in the past

2 : the process of development of an animal or a plant


evo·lu·tion | \ˌev-ə-ˈlü-shən also ˌē-və-\

Medical Definition of evolution 

1 : a process of change in a certain direction tumor evolution and progression— I. J. Fidler et al

2a : the historical development of a biological group (as a race or species) : phylogeny

b : a theory that the various types of animals and plants have their origin in other preexisting types and that the distinguishable differences are due to modifications in successive generations

Other Words from evolution

evolutionarily \-shə-ˌner-ə-lē \ adverb
evolutionary \-shə-ˌner-ē \ adjective

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