Definition of infectious
1a : capable of causing infection viruses and other infectious agentsb : 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
infectiously
adverbinfectiousness
nounIndulge Your Inner Word Nerd
Examples of infectious in a Sentence
viruses and other infectious agents
She has an infectious grin.
Recent Examples of infectious from the Web
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That's when an infectious disease researcher at the National institutes of Health first started noticing reports that clusters of young gay men were being diagnosed with infections that were highly unusual infections.
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Her infectious enthusiasm at every turn was one reason so many people came to support her May 29 in Georgia.
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President Trump has a magnetic personality and exudes positive energy, which is infectious to those around him.
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Her smile is as infectious as her heat vision is fierce.
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According to Facebook posts by family, he is expected to remain hospitalized for four to five days and an infectious disease specialist has been called in to evaluate the deputy.
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Ngozi Erondu, PhD, is an infectious disease epidemiologist and assistant professor at the London School of Hygiene and Tropical Medicine.
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The 32-year-old Cuban tres player San Miguel brings the infectious spirit and everyday lyrics of traditional Cuban son to music with pop appeal.
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Three volunteers come to our meetings regularly: a doctor who’s an expert in infectious disease, a gynecologist, and a psychologist.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infectious'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use of infectious
1534
INFECTIOUS Defined for English Language Learners
infectious
playDefinition of infectious for English Language Learners
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: capable of causing infection
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: capable of being passed to someone else by germs that enter the body
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: suffering from a disease that can be spread to other people by germs
INFECTIOUS Defined for Kids
infectious
playDefinition of infectious for Students
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
playMedical 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
infectiously
adverbinfectiousness
nounLearn More about infectious
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Thesaurus: All synonyms and antonyms for infectious Spanish Central: Translation of infectious Nglish: Translation of infectious for Spanish speakers Britannica English: Translation of infectious for Arabic speakers
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