An infant is the more formal or specialised synonym for the common term baby, meaning the very young offspring of human beings. The term may also be used to refer to juveniles of other organisms. A newborn is, in colloquial use, an infant who is only hours, days, or up to one month old. In medical contexts, newborn or neonate refers to an infant in the first 28 days after birth; the term applies to premature, full term, and postmature infants.
