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

That growth requires a constant evolution of our management structure. Wolfgang Spahr, Billboard, "BMG Promotes Ben Katovsky to COO, Ama Walton to Global General Counsel," 13 July 2018 The change in posture instead mirrors the Trump administration’s evolution in many other areas, from the Iran deal to incipient trade wars. Benjamin Hart, Daily Intelligencer, "Giuliani: Trump Won’t Sit Down for Mueller Interview Without a Fight," 7 July 2018 Setnet skiffs have undergone an even more dramatic evolution. John Schandelmeier, Anchorage Daily News, "At Bristol Bay, there’s a changing of the guard at the boatyard," 7 July 2018 The evolution of emergency care in the United States is a fascinating story. Paul Seward, STAT, "Emergency departments: the ‘chewing gum and duct tape’ holding together U.S. health care," 3 July 2018 But the evolution of desserts at Cured is a sweet story in itself. Mike Sutter, San Antonio Express-News, "Review: Cured makes a 3½-star statement at the Pearl," 28 June 2018 Wochit The evolution of personal finance advice in the United States in the past 20 years has been nothing short of remarkable. Peter Dunn, Indianapolis Star, "Pete the Planner: First step you must take to financial security," 27 June 2018 The evolution of Overstock has been both deliberate and serendipitous. New York Times, "From Furniture to Cryptocurrency — Overstock Is on a Journey," 27 June 2018 The evolution of heels is a small reminder, though, of how many of the things that are simply assumed to be true about gender are in fact extremely contingent. Megan Garber, The Atlantic, "What High Heels Can Teach About Gendered ‘Truths’," 26 June 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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Statistics for evolution

Last Updated

13 Sep 2018

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Time Traveler for evolution

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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