ev·o·lu·tion
(ĕv′ə-lo͞o′shən, ē′və-)n.1. a. A gradual process in which something changes into a different and usually more complex or better form.
b. A result of this process; a development: Judo is an evolution of an earlier martial art.
2. Biology a. Change in the genetic composition of a population during successive generations, often resulting in the development of new species. The mechanisms of evolution include natural selection acting on the genetic variation among individuals, mutation, migration, and genetic drift.
b. The historical development of a related group of organisms; phylogeny.
3. Astronomy Change in the structure, chemical composition, or dynamical properties of a celestial object or system such as a planetary system, star, or galaxy. Evolution often changes the observable or measurable characteristics of the object or system.
4. A movement that is part of a set of ordered movements: naval evolutions in preparation for battle.
5. Mathematics The extraction of a root of a quantity.
[Latin ēvolūtiō, ēvolūtiōn-, from ēvolūtus, past participle of ēvolvere, to unroll; see evolve.]
ev′o·lu′tion·al, ev′o·lu′tion·ar′y (-shə-nĕr′ē) adj.
ev′o·lu′tion·ar′i·ly adv.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
evolution
(ˌiːvəˈluːʃən) n1. (Biology)
biology a gradual change in the characteristics of a population of animals or plants over successive generations: accounts for the origin of existing species from ancestors unlike them. See also
natural selection 2. a gradual development, esp to a more complex form: the evolution of modern art.
3. (Chemistry) the act of throwing off, as heat, gas, vapour, etc
4. a pattern formed by a series of movements or something similar
5. (Mathematics) an algebraic operation in which the root of a number, expression, etc, is extracted. Compare
involution6 6. (Military) military an exercise carried out in accordance with a set procedure or plan
[C17: from Latin ēvolūtiō an unrolling, from ēvolvere to evolve]
ˌevoˈlutionary, ˌevoˈlutional adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
ev•o•lu•tion
(ˌɛv əˈlu ʃən; esp. Brit. ˌi və-)
n. 1. any process of formation or growth; development: the evolution of the drama.
2. a product of development; something evolved.
3. Biol. a. change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift.
b. the development of a species or other group of organisms; phylogeny.
c. the theory that all existing organisms developed from earlier forms by natural selection; Darwinism.
4. a process of gradual, progressive change and development, as in a social or economic structure.
5. a motion incomplete in itself, but combining with coordinated motions to produce a single action, as in a machine.
6. a pattern formed by a series of movements: the evolutions of a figure skater.
7. Math. the extraction of a root from a quantity.
8. a military training exercise.
9. a movement executed by troops in formation.
ev`o•lu′tion•al, ev•o•lu′tion•ar′y, adj.
ev`o•lu′tion•al•ly, ev`o•lu`tion•ar′i•ly, adv.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ev·o·lu·tion
(ĕv′ə-lo͞o′shən) The process by which species of organisms arise from earlier life forms and undergo change over a long period of time through natural selection. The genetic makeup of populations of organisms can be traced using fossils and recent advances in DNA technology to determine the relationships between members of a given species. See also
natural selection. See Note at
Darwin.
Did You Know? Darwin's theory of evolution by natural selection assumed that tiny adaptations occur in organisms constantly over exceptionally long periods of time. Gradually, a new species develops that is distinct from its ancestors. In the 1970s, however, biologists Niles Eldredge and Stephen Jay Gould proposed that evolution by natural selection was a far more bumpy road. Based on types of fossils that exist around the world, they said that evolution is better described through punctuated equilibrium. That is, for long periods of time, species in fact remain virtually unchanged, not even gradually adapting. They are in equilibrium, in a balance with the environment. But when confronted with environmental challenges—sudden climate change, for example—organisms adapt quite quickly, perhaps in only a few thousand years. These active periods are punctuations, after which a new equilibrium exists and species remain stable until the next punctuation.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Evolution
the theory of evolution by natural selection of those species best adapted to survive the struggle for existence. — Darwinian, n., ad).
a principle or theory of evolution. — evolutionist, n., adj.
the theory of organic evolution advanced by the French naturalist Lamarck that characteristics acquired by habit, diseases, or adaptations to change in environment may be inherited. — Lamarckian, n., adj.
the theory that maintains natural selection to be the major factor in plant and animal evolution and denies the possibility of inheriting acquired characteristics. — Neo-Darwinist, n., adj. — Neo-Darwinian, n., adj.
a modern theory based on Lamarckism that states that acquired characteristics are inherited. — Neo-Lamarckian, n., adj.
progressive evolution, leading to the development of a new form, as can be seen through successive generations. See also
society. —
orthogenetic,
adj.
the theory advanced by Darwin, now rejected, that each part of the body is represented in each cell by gemmules, which are the basic units of hereditary transmission. — pangenetic, adj.
the history of the development of a plant, animal, or racial type. — phylogenist, n. — phylogenetic, adj.
a devotion to the conditions which existed at the beginning of creation.
the ability of one species to change into another. — transformist, n.
1. the theory that chance is involved in evolution and that variation within a species is accidental.
2. the belief that chance rather than mere determinism operates in the cosmos. Cf. uniformitarianism.
1. Philosophy. a doctrine that the universe is governed only by rigid, unexceptionable law.
2. Geology. the concept that current geological processes explain all past geological occurrences. — uniformitarian, n., adj.
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.
evolution
Change in the characteristics of a population of organisms over time.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited