The theory that organisms develop features during their lifetime that did not exist in their ancestors, or the acquisition of new characteristics in the course of an organism's development.
From Greek kainos (new) + genesis (origin, creation). The term emerged in 19th-century evolutionary and developmental biology discussions.
This concept challenged Darwin's ideas—it suggested that new traits could appear suddenly in individuals rather than slowly through natural selection over generations, though modern biology has largely moved past this theory.
Complete word intelligence in one call. Free tier — 50 lookups/day.