Evolution

n. development, progression, unfolding, growth; gradual change in the gene pool (Biology)

In biology, evolution is the change in the inherited traits of a population from generation to generation. These traits are the expression of genes that are copied and passed on to offspring during reproduction. Mutations in these genes can produce new or altered traits, resulting in heritable differences (genetic variation) between organisms. New traits can also come from transfer of genes between populations, as in migration, or between species, in horizontal gene transfer. Evolution occurs when these heritable differences become more common or rare in a population, either non-randomly through natural selection or randomly through genetic drift.
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Noun
1. a process in which something passes by degrees to a different stage (especially a more advanced or mature stage); "the development of his ideas took many years"; "the evolution of Greek civilization"; "the slow development of her skill as a writer"
(synonym) development
(antonym) degeneration, devolution
(hypernym) process
(hyponym) assibilation
(derivation) evolve
2. (biology) the sequence of events involved in the evolutionary development of a species or taxonomic group of organisms
(synonym) phylogeny, phylogenesis
(hypernym) organic process, biological process
(hyponym) anamorphosis, anamorphism
(derivation) develop, acquire, evolve
(classification) biology, biological science
(class) Scopes trial

n. evolution, development, progression, gradual change in the gene pool (Biology)

n. evolution, development, change, growth, advancement