Definition of: evolution

(ev′ə·l′shən) noun
1. The act or process of unfolding; development or growth, usually in slow stages and from simpler forms to those which are more complex: the evolution of the telephone.
2. Biol. a The doctrine that all forms of life originated by descent, with gradual or abrupt modifications, from preexisting forms which themselves trace backward in a continuing series to the most rudimentary organisms. b The series of changes by which a given type of organism has acquired the physiological and structural characteristics differentiating it from other types; phylogeny.
3. The old theory of preformation, that the germ contains all the parts of the mature organism in minute form; development from such a germ: opposed to epigenesis.
4. Math. The operation of extracting a root.
5. A move or maneuver, as of troops.
6. Philos. The cosmological theory that accounts for the universe and its contents by the combination of separate and diffused atoms existing originally in a condition of absolute homogeneity.
7. A movement forming one of a series of complex motions; hence, any intricate or involved form: the evolutions of the labyrinth.
8. Anything evolved; also, a series unfolded.
—ev′o·lu′tion·al adjective
—ev′o·lu′tion·al·ly adverb
—ev′o·lu′tion·ism noun
—ev′o·lu′tion·ist adjective & noun