evolution

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

Updated on: 10 May 2018

Definition of evolution

1 a : 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

2 a : 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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evolutionarily

play \ˌe-və-ˈlü-shə-ˌner-ə-lē, ˌē-və-\ adverb

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evolutionary

play \ˌe-və-ˈlü-shə-ˌner-ē, ˌē-və-\ adjective

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evolutionism

play \ˌe-və-ˈlü-shə-ˌni-zəm, ˌē-və-\ noun

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evolutionist

play \ˌe-və-ˈlü-sh(ə-)nist, ˌē-və-\ noun or adjective

See evolution defined for English-language learners

See evolution defined for kids

Examples of evolution in a Sentence

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

Recent Examples of evolution from the Web

Such encoding has also led, over millions of years of evolution, to salmon that are uniquely adapted to their home rivers.

— katie langin, Science | AAAS, "Salmon spawn fierce debate over protecting endangered species, thanks to a single gene," 4 May 2018
Now, high-tech analyses of four fossilized three-dimensional skulls provide tantalizing hints about what the beak of this iconic creature might have looked like as well as clues about the evolution of early birds.

— sid perkins, Scientific American, "New Fossils Offer Clues about a Primordial Bird Beak," 2 May 2018
In one episode from the sitcom Friends, Phoebe and Ross argue about evolution.

— nikk effingham, Vox, "How to argue with flat earthers," 28 Apr. 2018
So there was this time of evolution, and that time was the Justice League of America, a group setting out to address problems differently with a community mindset.

— graeme mcmillan, The Hollywood Reporter, "'Justice League of America' Writer Dissects a Year of Storytelling," 27 Apr. 2018
Billions of years of evolution have given us these incredible proteins, which science is just beginning to characterize.

— megan molteni, WIRED, "A New Startup Wants to Use Crispr to Diagnose Disease," 26 Apr. 2018
Recently, the band’s lead singer, songwriter and guitarist Ric Ocasek, lead guitarist Elliot Easton, drummer David Robinson and former radio disc jockey Maxanne Sartori talked about the song’s evolution.

— marc myers, WSJ, "The Story Behind the Cars’ ‘My Best Friend’s Girl’," 23 Apr. 2018
Darwin’s ideas about evolution were based on the observable characteristics of his finches.

— kat eschner, Smithsonian, "What We Can Learn From a New Bird Tree of Life," 21 Apr. 2018
And part of that evolution is the empathy for Alice.

— megan stielstra, Longreads, "Maybe We’re the Circle," 19 Apr. 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.

Origin and Etymology of evolution

Latin evolution-, evolutio unrolling, from evolvere

NEW! Time Traveler

First Known Use: 1616

in the meaning defined at sense 6

See Words from the same year

evolution Synonyms

EVOLUTION Defined for Kids

evolution

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

Definition of evolution for Students

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

Medical Dictionary

evolution

noun 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

2 a : 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

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