infantile

Infantile is an adjective that generally relates to infants or infancy. It can describe characteristics arising in early life, such as developmental stages or medical conditions that begin in infancy. In broader usage, infantile can also mean immature or childish, especially when referring to behavior or attitudes in adults.

Etymology and scope: The term derives from the Latin infantilis, from infans meaning infant, and was historically linked to speech and development. In scientific and clinical contexts, infantile denotes something pertaining to or occurring during infancy, typically the period from birth to about one year of age, though some medical terms extend into early childhood.

Medical and scientific uses: Many conditions are labeled with infantile in their name to indicate onset in infancy. Examples include infantile colic (unexplained crying in infants), infantile eczema (atopic dermatitis in babies), and infantile spasms (a type of epilepsy in young children). Infantile paralysis historically referred to poliomyelitis and is now largely replaced by more specific terminology. The term infantile autism has largely been superseded by autism spectrum disorder with onset in early childhood. In psychology, infantile amnesia refers to the common but incomplete memory of early life.

Contemporary usage: While still used in medical and historical contexts, infantile is sometimes avoided in everyday language due to potential pejorative connotations of “infantile” as childish or immature. Clinically, practitioners prefer precise terminology about the condition and its onset.

See also: infancy, infancy development, infancy-related disorders, autism spectrum disorder, developmental psychology.