noun.
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noun.
Disease transmission by direct or indirect contact.
noun.
A disease that is or may be transmitted by direct or indirect contact; a contagious disease.
noun.
The direct cause, such as a bacterium or virus, of a communicable disease.
noun.
The spread of a behavior pattern, attitude, or emotion from person to person or group to group through suggestion, propaganda, rumor, or imitation.
noun.
A harmful, corrupting influence.
noun.
The tendency to spread, as of a doctrine, influence, or emotional state.