tr.v. in·fect·ed, in·fect·ing, in·fects
1. To invade and proliferate in, often resulting in disease. Used of microorganisms or other infectious agents: people who were infected with salmonella.
2. To cause the invasion of (a cell, for example) with a microorganism or other infectious agent: The researchers infected the bacteria with a virus.
3. To transmit a pathogen or disease to: The sick child infected the entire class.
4. To contaminate with a pathogenic microorganism or agent: Cholera infected the water supply.
5. Computers To become transmitted to and copied on (a hard drive, for example). Used of a virus or other harmful software.
6. To affect by transmission or be communicated to. Used of an idea, emotion, or attitude: "His fear infected me, and ... I followed as fast as I could" (W.H. Hudson).
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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