To infect is to spread an illness to another person. If you sneeze on your friend, you may inadvertently infect her with your germs.

When a disease moves from person to person, it infects them. Most diseases only spread within one species, although there are some, like avian flu, that can infect both humans and other animals. Another way to infect someone is to deeply affect them with an idea or emotion: "His enthusiasm for music infects the class with excitement." The Latin root, inficere, means "to spoil or stain" and "to dip into."

Definitions of infect
  1. verb
    contaminate with a disease or microorganism
    synonyms: taint
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    destroy microorganisms or pathogens by cleansing
    infect (an infected cell) further or infect a cell already containing similar organisms
    affect with smut or mildew, as of a crop such as corn
    type of:
    contaminate, foul, pollute
    make impure
  2. verb
    communicate a disease to
    “Your children have infected you with this head cold”
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    infect with a canker
    type of:
    cause to have, in the abstract sense or physical sense
  3. verb
    affect in a contagious way
    “His laughter infects everyone who is in the same room”
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    type of:
    affect, impress, move, strike
    have an emotional or cognitive impact upon
  4. verb
    corrupt with ideas or an ideology
    “society was infected by racism”
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    type of:
    corrupt, debase, debauch, demoralise, demoralize, deprave, misdirect, pervert, profane, subvert, vitiate
    corrupt morally or by intemperance or sensuality
Word Family

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