The definition of a disease is an illness or sickness with specific, well-defined symptoms that affects a person, plant or animal.(noun)
An example of a disease is cancer.
See disease in Webster's New World College Dictionary
Origin: ME disese, inconvenience, trouble, sickness < OFr desaise, discomfort < des-, dis- + aise, ease
See disease in American Heritage Dictionary 4
Origin: Middle English disese
Origin: , from Old French
Origin: : des-, dis-
Origin: + aise, ease; see ease.
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