1. The processes of biological and organic changes in organisms by which descendants grow and thrive differently from their ancestors: Evolutions are supposed to have made more advanced or mature developments of humans.
2. The gradual process of something into a more complex or better form: Evolution is the continuing series of actions from one state or condition to another or from one shape to another.
3. The theoretical amount by which all species develop from earlier forms of life: According to this theory of evolution, it is a natural variation in the genetic material of a population that favors reproduction by some individuals more than others; so that, over the generations all members of certain inhabitants have come to possess the favorable or unfavorable modern traits as shown in the illustration below.

Any fundamental change over time in the social and economic character of a given society.

Specifically, an earlier theory that cultures will naturally pass through certain progressive stages on the path to industrialization; that is, from hunger-gatherer societies to nomadism, to agricultural and pastoralism, and then ultimately to a modern industrial society.

Over geological time any change in the chemical composition of some section of the Earth: Geochemical evolution is an important factor in the oceans.

Geochemical evolution is any alteration or change in the chemical composition of a rock in which the amount of a particular component exceeds the amount present in the parent rock.

The appearance of a sudden change within a species, caused by mutation: Saltatory evolution involves the progression of a species by sudden major changes rather than by the gradual accumulation of minor changes.

The phenomena of saltatory evolutions occur predominantly in plants as a result of having one or more extra sets of chromosomes or DNA that are encoded with genes and structural proteins.