Intellectual delay also known as developmental delay where a child does not reach the same level of functioning in one or more major life activities such as self -care, language, learning , mobility, self-direction, independent living, and economic self-sufficiency.
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Intellectual Delay is where a child does not reach the same level of functioning in one or more major life activities such as self-care, language, learning, mobility, self-direction, independent living, and economic self-sufficiency.

Intellectual Delay is also known as "Developmental Delay".
A list of books about the topic Intellectual delay