Hypoplasia

Underdevelopment of a tissue or organ

Hypoplasia is underdevelopment or incomplete development of a tissue or organ. Although the term is not always used precisely, it properly refers to an inadequate or below-normal number of cells. Hypoplasia is similar to aplasia, but less severe. It is technically not the opposite of hyperplasia. Hypoplasia is a congenital condition, while hyperplasia generally refers to excessive cell growth later in life.

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