noun, verb, -eased, -eas⋅ing.| 1. | 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 or imbalance, toxicity, or unfavorable environmental factors; illness; sickness; ailment. |
| 2. | any abnormal condition in a plant that interferes with its vital physiological processes, caused by pathogenic microorganisms, parasites, unfavorable environmental, genetic, or nutritional factors, etc. |
| 3. | any harmful, depraved, or morbid condition, as of the mind or society: His fascination with executions is a disease. |
| 4. | decomposition of a material under special circumstances: tin disease. |
| 5. | to affect with disease; make ill. |
disease dis·ease (dĭ-zēz')
n.
A pathological condition of a body part, an organ, or a system resulting from various causes, such as infection, genetic defect, or environmental stress, and characterized by an identifiable group of signs or symptoms.
disease
a harmful deviation from the normal structural or functional state of an organism. A diseased organism commonly exhibits signs or symptoms indicative of its abnormal state. Thus, the normal condition of an organism must be understood in order to recognize the hallmarks of disease. Nevertheless, a sharp demarcation between disease and health is not always apparent
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