- The definition of preschool is someone or something related to children too young to attend school.
A book catering to 2-5 year old children is an example of a book that would be described as a preschool book.
- Preschool is an educational program or school environment targeted to young children before they attend kindergarten.
A school for children ages 2-5 who are too young for kindergarten is an example of preschool.
(comparative more preschool, superlative most preschool)