plasia

Plasia is a suffix used in medical terminology to denote growth, formation, or development of tissue, cells, or organs. It appears in numerous terms that describe patterns of tissue change, and by itself it does not indicate disease. The root comes from Greek plasis, meaning molding or formation, and it is commonly used in pathology and histology to describe how tissues change in size, structure, or function.

Common terms derived from plasia include hyperplasia, hypoplasia, aplasia, dysplasia, and metaplasia. Hyperplasia refers to an increase in the number of cells within a tissue, leading to enlargement; it can be physiologic, such as hormonal or compensatory hyperplasia, or pathologic, as in some diseases. Hypoplasia describes underdevelopment or incomplete growth of a tissue or organ. Aplasia denotes failure of an organ or tissue to develop. Dysplasia indicates disordered growth with abnormal cell organization and appearance, often considered precancerous due to heightened risk of progression to malignancy. Metaplasia is the reversible transformation of one differentiated cell type into another, typically as an adaptive response to stress or injury. The term neoplasia, meaning new growth, is related and describes abnormal, uncontrolled tissue growth that can be benign or malignant.

Clinical interpretation of -plasia terms depends on context; not all such conditions imply cancer. Some are normal physiological processes (for example, endometrial or glandular hyperplasia during certain life stages), while others signal potential pathology requiring monitoring or treatment.