1. An abnormal condition of a part, organ, or system of an organism resulting from various causes, such as infection, inflammation, environmental factors, or genetic defect, and characterized by an identifiable group of signs, symptoms, or both.
2. A condition or tendency, as of society, regarded as abnormal and harmful.
3. Obsolete Lack of ease; trouble.
[Middle English disese, from Old French : des-, dis- + aise, ease; see EASE.]
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