Childism can refer either to advocacy for empowering children as a subjugated group or to prejudice and/or discrimination against children or childlike qualities.^[1] It can operate thus both as a positive term for a movement, like the term feminism, as well as a critical term to identify age-based prejudice and discrimination against children, like the term racism. The latter concept finds it critical equivalence in similar concepts such as ageism discrimination against elderly people,^[2] adultism adult power and adult norms ^[3]or patriarchy. The concept is first described and explored in an article by Chester M. Pierce and Gail B. Allen in 1975.^[4] It was used in time in the 1990s in literary theory by Peter Hunt to refer to "to read as children."^[5] An extensive treatment of childism as a negative phenomenon is found in Elisabeth Young-Bruehl's last work, published posthumously, Childism: Confronting Prejudice Against Children.^[6]

In the field of childhood studies, and most commonly in Europe, childism is a positive phenomenon based on John Wall's work since 2006 and book, Ethics in Light of Childhood.^[7] Recently, the Childism Institute has been formed at Rutgers University Camden, US, holding its inaugural meeting on 11 June 2020. The Childism Institute is a network of international researchers and advocates devoted to "empowering children by critiquing [adultist] norms and structures".^[8] Among other things, the Childism Institute maintains a database of research which either employs the concept of childism or is in close alignment with it.

In the field of international human rights studies childism is a critical phenomenon based on Elisabeth Young-Bruehl's work, used to explore intersectional discrimination against children that challenge the implementation of the Convention on the Rights of the Child.^[9]