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evolution

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

biology : a theory that the differences between modern plants and animals are because of changes that happened by a natural process over a very long time

: the process by which changes in plants and animals happen over time

: a process of slow change and development

Full Definition of EVOLUTION

: one of a set of prescribed movements

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

: the process of working out or developing

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; also : the process described by this theory

: the extraction of a mathematical root

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

— evo·lu·tion·ari·ly \-shə-ˌner-ə-lē\ adverb

— evo·lu·tion·ary \-shə-ˌner-ē\ adjective

— evo·lu·tion·ism \-shə-ˌni-zəm\ noun

— evo·lu·tion·ist \-sh(ə-)nist\ noun or adjective

See evolution defined for English-language learners

See evolution defined for kids

Origin of EVOLUTION

Latin evolution-, evolutio unrolling, from evolvere

First Known Use: 1622

Related to EVOLUTION

Synonyms: elaboration, development, expansion, growth, progress, progression

Antonyms: regress, regression, retrogression, reversion

EVOLUTIONARY Defined for Kids

evolution

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

Definition of EVOLUTION for Kids

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

: 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

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

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

—evo·lu·tion·ari·ly \-shə-ˌner-ə-lē\ adverb

—evo·lu·tion·ary \-shə-ˌner-ē\ adjective