The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time
Note générale sur le champ d'application :
human & animal; IM; aging process anywhere between birth & old age; differentiation from other age-related terms: Manual 28.16, 34.10; "aging" of lower organisms, cultures, drugs, etc. is probably TIME FACTORS; AGING, PREMATURE is also available