Meaning : A process in which something passes by degrees to a different stage (especially a more advanced or mature stage).
Example :
The development of his ideas took many years.
The evolution of Greek civilization.
The slow development of her skill as a writer.
Synonyms : development
The process of declining from a higher to a lower level of effective power or vitality or essential quality.
degeneration, devolutionMeaning : (biology) the sequence of events involved in the evolutionary development of a species or taxonomic group of organisms.
Synonyms : organic evolution, phylogenesis, phylogeny