The English language has several terms for children between the ages of birth and 4 years, including newborn, infant, baby, and toddler. The terms are often used interchangeably and may mean different things to different people. Here's a look at each of these terms, what age range they apply to, and an overview of the growth and development you can expect during that time.
Babies, Newborns, and Infants
Though the terms "baby", "newborn" and "infant" are frequently used synonymously, the exact definition depends on the source you consult.
- Newborn usually refers to a baby from birth to about 2 months of age.
- Infants can be considered children anywhere from birth to 1 year old.
- Baby can be used to refer to any child from birth to age 4 years old, thus encompassing newborns, infants, and toddlers.
The Merriam-Webster dictionary simply says a newborn is a child who is recently born and does not put an upper limit to the term. Merriam-Webster also defines an infant as a child in the first stage of life but doesn't give any age specifics and describes a baby as "an extremely young child." The World Health Organization (WHO) defines a newborn, infant, or neonate, as a child that's under 28 days old.
Growth and Development