| Noun | 1. | dysplasia - abnormal development (of organs or cells) or an abnormal structure resulting from such growth aplasia - failure of some tissue or organ to develop fibrous dysplasia of bone - a disturbance in which bone that is undergoing lysis is replaced by an abnormal proliferation of fibrous tissue resulting in bone lesions or skin lesions hypertrophy - abnormal enlargement of a body part or organ hyperplasia - abnormal increase in number of cells hypoplasia - underdevelopment of an organ because of a decrease in the number of cells anaplasia - loss of structural differentiation within a cell or group of cells often with increased capacity for multiplication, as in a malignant tumor abnormalcy, abnormality - an abnormal physical condition resulting from defective genes or developmental deficiencies |