Neonatal describes the first month of a person's life. The neonatal period is that first month after a baby is born. There are also neonatal disorders that require neonatal care.
Like many babies, the word neonatal's parents are from different places — neo comes from Greek and means “new,” and natal comes from the Latin word natus which means “to be born.” Neonatal means newborn. The neonatal stage is the first month of life, when a baby is tiniest and most fragile. Babies born at a hospital who can’t come home right away sometimes stay in a neonatal intensive care unit, where neonatal nurses care for them.