There are four main types of disease: infectious diseases, deficiency diseases, hereditary diseases (including both genetic and non-genetic hereditary diseases), and physiological diseases. Diseases …

Dec 12, 2025 · disease, any harmful deviation from the healthy structural or functional state of an organism, generally associated with certain signs and symptoms and differing in nature from physical …

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Jun 5, 2025 · Osteoporosis is a bone disease that develops when the bones get weaker and less dense. When a child or teen develops osteoporosis, the condition is known as juvenile osteoporosis.

Jun 1, 2025 · At first glance, the answer seems deceptively simple: disease is the presence of illness, of something going wrong within the body. But the deeper we probe into this question—scientifically, …

DISEASE definition: 1. (an) illness of people, animals, plants, etc., caused by infection or a failure of health rather…. Learn more.

DISEASE definition: a disordered or incorrectly functioning organ, part, structure, or system of the body resulting from the effect of genetic or developmental errors, infection, poisons, nutritional deficiency …

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Mar 7, 2025 · What’s the definition of a disease? A disease is a disorder that interferes with your body’s normal functions. “Typically, a disease is something that your physician diagnoses, using a …