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

v contaminate with a disease or microorganism

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

v communicate a disease to

“Your children have infected you with this head cold”
infect with a canker
Type of:
cause to have, in the abstract sense or physical sense

v affect in a contagious way

“His laughter infects everyone who is in the same room”
Type of:
affect, impress, move, strike
have an emotional or cognitive impact upon

v corrupt with ideas or an ideology

“society was infected by racism”
Type of:
corrupt, debase, debauch, demoralise, demoralize, deprave, misdirect, pervert, profane, subvert, vitiate
corrupt morally or by intemperance or sensuality

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