Developmental delay

Developmental disability is a term used to describe life-long disabilities attributable to mental and/or physical or combination of mental and physical impairments, manifested prior to age twenty-two. The term is used most commonly in the United States to refer to disabilities affecting daily functioning in three or more of the following areas:capacity for independent livingeconomic self-sufficiencylearningmobilityreceptive and expressive languageself-careself-direction
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Developmental delay n. A chronological delay in the appearance of normal developmental milestones achieved during infancy and early childhood, [more]Developmental delay - Community and Resources

Behind schedule in reaching milestones of early childhood development.