degeneration (suomeksi)

rappeutuminen (s: lajin geeneistä / process or state of growing worse / gradual deterioration, from natural causes, of any class of animals or plants)
taantuminen (s: process or state of growing worse)
rappeuma (s: condition of a tissue or an organ in which its vitality has become diminished / something degenerated)
degeneraatio (s: gradual deterioration, from natural causes, of any class of animals or plants)