- A child up to 2 years (24 months) of age. The word "infant" came from the Latin infans which was derived from in-, not + Fari, to speak = not to speak, speechless. The idea was that, since the ability to speak was thought to arrive at the age of two, younger children were infants. By an odd twist, some adults may only show their infantile attitudes when they open their mouths to speak.
* * *A child under the age of 1 year. [L. infans, not speaking]- i. Hercules term applied to young children with precocious sexual and muscular development due to a virilizing adrenocortical disorder.- liveborn i. the product of a livebirth; an i. who shows evidence of life after birth; life is considered to be present after birth if any one of the following is observed: 1) if the i. breathes; 2) if the i. shows beating of the heart; 3) if pulsation of the umbilical cord occurs; or 4) if there is definite movement of voluntary muscles.- postmature i. a baby born after over 42 weeks of gestation, which puts the child at risk because of inadequate placental function. The i. usually shows wrinkled skin, sometimes more serious abnormalities.- postterm i. an i. with a gestational age of 42 completed weeks or more (294 days or more).- preterm i. an i. with gestational age of more than 20 weeks and less than 37 completed weeks (259 completed days).- stillborn i. an i. who has achieved 20 weeks of gestation and shows no evidence of life after birth. Cf.:liveborn i..- term i. an i. with gestational age between 37 completed weeks (259 completed days) and 42 completed weeks (294 completed days).
* * *in·fant 'in-fənt n1 a) a child in the first year of life: BABYb) a child several years of age2) a person who is not of full age: MINORinfant adj
* * *n.a child incapable of any form of independence from its mother: the term is usually used to refer to a child under one year of age, especially a premature or newborn child. In legal use the term denotes a child up to the age of seven years.
* * *in·fant (inґfənt) a young child; considered to designate the human young from birth (see neonate) to 12 months.
Medical dictionary. 2011.