- any departure from health; illness in general
- a particular destructive process in an organ or organism, with a specific cause and characteristic symptoms; specif., an illness; ailment
- any harmful or destructive condition, as of society
Origin of diseaseMiddle English disese, inconvenience, trouble, sickness from Old French desaise, discomfort from des-, dis- + aise, ease
transitive verb-·eased′, -·eas′ing
Origin of diseaseME disesen < OFr desaaisier < the n.