obesity: Body Mass Index for adultsEncyclopÃ¦dia Britannica, Inc.Obesity was traditionally defined as an increase in body weight that was greater than 20 percent of an individualâs ideal body weightâthe weight associated with the lowest risk of death, as determined by certain factors, such as age, height, and gender.
Define infancy: early childhood; a beginning or early period of existence; the legal status of an infant â infancy in a sentence early childhood; a beginning or early period of existence; the legal status of an infantâ¦ See the full definition
Infant is a more formal term for a baby, the youngest category of child. A child is no longer considered an infant when able to walk and talk, which, in most cases, is at about 1 year. The term child covers the age range from birth to puberty.