The definition of contagion is an infectious disease spread through contact, or the transmission of a disease from one person to another through contact, or the spread of a bad or harmful idea or practice.(noun)
See contagion in Webster's New World College Dictionary
Origin: ME contagioun < L contagio, a touching < contingere: see contact
See contagion in American Heritage Dictionary 4
Origin: Middle English contagioun
Origin: , from Latin contāgiō, contāgiōn-
Origin: , from contingere, contāct-, to touch; see contact.
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