Dictionary
infectious
adjective in·fec·tious \-shəs\
: capable of causing infection
: capable of being passed to someone else by germs that enter the body
: suffering from a disease that can be spread to other people by germs
Full Definition of INFECTIOUS
1
a : capable of causing infection <viruses and other infectious agents> b : communicable by infection <an infectious disease> — compare contagious
2
: that corrupts or contaminates
3
: spreading or capable of spreading rapidly to others <their enthusiasm was infectious> <an infectious grin>
— in·fec·tious·ly adverb
— in·fec·tious·ness noun
See infectious defined for English-language learners
See infectious defined for kids
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First Known Use of INFECTIOUS
1542
Related to INFECTIOUS
- Synonyms
- catching, epidemic, contagious, spreading
INFECTIOUSNESS Defined for Kids
infectious
adjective in·fec·tious \in-ˈfek-shəs\
Definition of INFECTIOUS for Kids
1
: passing from one to another in the form of a germ <an infectious illness>
2
: easily spread to others <an infectious laugh>
Medical Dictionary
infectious
adjective in·fec·tious \in-ˈfek-shəs\
Medical Definition of INFECTIOUS
1
: capable of causing infection <a carrier remains infectious without exhibiting signs of disease> <viruses and other infectious agents>
2
: communicable by invasion of the body of a susceptible organism <all contagious diseases are also infectious, but it does not follow that all infectious diseases are contagious—W. A. Hagan>—compare contagious 1
—in·fec·tious·ly adverb
—in·fec·tious·ness noun
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