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

Definition of evolution

  1. 1 :  one of a set of prescribed movements

  2. 2a :  a process of change in a certain direction :  unfoldingb :  the action or an instance of forming and giving something off :  emissionc (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 advanced :  something evolved

  3. 3 :  the process of working out or developing

  4. 4a :  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 Weintraubb :  the historical development of a biological group (such as a race or species) :  phylogeny

  5. 5 :  the extraction of a mathematical root

  6. 6 :  a process in which the whole universe is a progression of interrelated phenomena


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


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


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


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

Examples of evolution in a sentence

  1. changes brought about by evolution

  2. an important step in the evolution of computers

Did You Know?

Part of the humor of the old Flintstones cartoon show is that it contradicts what is known about biological evolution, since humans actually evolved long after dinosaurs were extinct. Evolution can also be used more broadly to refer to technology, society, and other human creations. For example, an idea may evolve, even in your own mind, as the months or years pass. And though many people don't believe that human beings truly become better with the passing centuries, many will argue that our societies tend to evolve, producing more goods and providing more protection for more people.

Origin and Etymology of evolution

Latin evolution-, evolutio unrolling, from evolvere

First Known Use: 1616

EVOLUTION Defined for Kids


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

Definition of evolution for Students

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

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

Medical Dictionary


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

Medical Definition of evolution

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

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


\-shə-ˌner-ə-lē\play adverb


\-shə-ˌner-ē\play adjective

Seen and Heard

What made you want to look up evolution? Please tell us where you read or heard it (including the quote, if possible).


holding stubbornly to a belief or view

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