infectious

play
adjective in·fec·tious \-shəs\

Definition of infectious

  1. 1 a :  capable of causing infection <viruses and other infectious agents> b :  communicable by infection <an infectious disease> — compare contagious

  2. 2 :  that corrupts or contaminates

  3. 3 :  spreading or capable of spreading rapidly to others <their enthusiasm was infectious> <an infectious grin>

infectiously

adverb

infectiousness

noun

Examples of infectious in a sentence

  1. viruses and other infectious agents

  2. She has an infectious grin.

1542

First Known Use of infectious

1542


INFECTIOUS Defined for English Language Learners

infectious

play
adjective in·fec·tious \-shəs\

Definition of infectious for English Language Learners

  • : 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


INFECTIOUS Defined for Kids

infectious

play
adjective in·fec·tious \in-ˈfek-shəs\

Definition of infectious for Students

  1. 1 :  passing from one to another in the form of a germ <an infectious illness>

  2. 2 :  easily spread to others <an infectious laugh>


Medical Dictionary

infectious

play
adjective in·fec·tious \in-ˈfek-shəs\

Medical Definition of infectious

  1. 1:  capable of causing infection <a carrier remains infectious without exhibiting signs of disease> <viruses and other infectious agents>

  2. 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

infectiously

adverb

infectiousness

noun


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