Pronunciation /ivlu()n//vlu()n/nounmass noun

1The process by which different kinds of living organism are believed to have developed from earlier forms during the history of the earth.

The idea of organic evolution was proposed by some ancient Greek thinkers but was long rejected in Europe as contrary to the literal interpretation of the Bible. Lamarck proposed a theory that organisms became transformed by their efforts to respond to the demands of their environment. Lyell demonstrated that geological deposits were the cumulative product of slow processes over vast ages. This helped Darwin towards a theory of gradual evolution over a long period by the natural selection of those varieties of an organism slightly better adapted to the environment and hence more likely to produce descendants. Combined with the later discoveries of the cellular and molecular basis of genetics, Darwin's theory of evolution has, with some modification, become the dominant unifying concept of modern biology

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2The gradual development of something.

the forms of written languages undergo constant evolution

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Synonyms

development, advancement, growth, rise, progress, progression, expansion, extension, unfolding

3Chemistry The giving off of a gaseous product, or of heat.

the evolution of oxygen occurs rapidly in this process

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4count noun A pattern of movements or manoeuvres.

flocks of waders often perform aerial evolutions

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5Mathematics dated The extraction of a root from a given quantity.

Early 17th century: from Latin evolutio(n-) unrolling, from the verb evolvere (see evolve). Early senses related to movement, first recorded in describing a wheeling manoeuvre in the realignment of troops or ships. Current senses stem from a notion of opening out, giving rise to the sense development.

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evolution | Definition of evolution in English by Oxford ...