Of, relating to, or of the nature of an epidemic; widespread and rapid in affecting many people.
From Greek 'epidemos' + English suffix '-ical'. This is a less common variant of 'epidemic' as an adjective, used historically in medical literature.
'Epidemical' is an older form—nowadays doctors say 'epidemic' or 'epidemiological'—but it means the same thing: a disease spreading fast through a population!
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