Neonate / Newborn (Birth – 28 days)
Infant: (1mo – 1yr)
Toddler: (1 – 3 yrs)
Preschooler: (3 – 5 yrs)
Youth & Adolescence
Middle Childhood (6 – 12 yrs)
Adolescent / Teenager (10 – 19 yrs)
Adulthood
Young Adult: (20 – 39 yrs)
Middle-aged Adult: (40 – 64 yrs)
Geriatrics
Young-Old: (65 – 74 yrs)
Old-Old: (75 – 84 yrs)
Oldest-Old: (85 yrs +)