n. 1. a. Disease transmission by direct or indirect contact. b. A disease that is or may be transmitted by direct or indirect contact; a contagious disease. c. The direct cause, such as a bacterium or virus, of a communicable disease. 2. Psychology The spread of a behavior pattern, attitude, or emotion from person to person or group to group through conscious or unconscious imitation. 3. A harmful, corrupting influence: feared that violence on television was a contagion affecting young viewers. 4. The tendency to spread, as of a doctrine, influence, or emotional state. [Middle English contagioun, from Latin contāgiō, contāgiōn-, from contingere, contāct-, to touch; see CONTACT.] |
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