An infant (from the Latin word infans, meaning unable to speak or speechless) is the more formal or specialised synonym for baby, the very young offspring of a human or other animal.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 (from Latin, neonatus, newborn) refers to an infant in the first 28 days after birth; the term applies to premature, full term, and postmature infants; before birth, the term fetus is used. The term infant is typically applied to young children between one month and one year of age; however, definitions may vary and may include children up to two years of age. When a human child learns to walk, the term toddler may be used instead.In British English, infant is a term that can be applied to school children aged between four and seven. As a legal term, infancy continues from birth until age 18.
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