infectious

[ in-fek-shuhs ]

/ ɪnˈfɛk ʃəs /

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See synonyms for infectious on Thesaurus.com

adjective

communicable by infection, as from one person to another or from one part of the body to another: infectious diseases.

causing or communicating infection.

tending to spread from one to another: infectious laughter.

Law. capable of contaminating with illegality; exposing to seizure or forfeiture.

Obsolete. diseased.

OTHER WORDS FOR infectious

1 catching.

See synonyms for infectious on Thesaurus.com

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Origin of infectious

First recorded in 1535–45; infect(ion) + -ious

synonym study for infectious

1. See contagious.

OTHER WORDS FROM infectious

in·fec·tious·ly, adverbin·fec·tious·ness, nounnon·in·fec·tious, adjectivenon·in·fec·tious·ly, adverb

non·in·fec·tious·ness, nounun·in·fec·tious, adjectiveun·in·fec·tious·ly, adverbun·in·fec·tious·ness, noun

WORDS THAT MAY BE CONFUSED WITH infectious

contagious, infectious (see synonym study at contagious)

Words nearby infectious

in favor with, infeasible, infect, infectee, infection, infectious, infectious anemia of horses, infectious bovine rhinotracheitis, infectious canine hepatitis, infectious disease, infectious diseases

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use infectious in a sentence

If you’re sleeping in a bed with them, sharing your home with them, and so on, you already have a decent risk of swapping the virus, or really any other infectious disease.
How to celebrate Valentine’s Day in a pandemic|Sara Kiley Watson|February 10, 2021|Popular-Science
Monica Gandhi, an infectious disease doctor and a professor of medicine at the University of California San Francisco, said the focus on transmission in the context of Covid-19 vaccines can be misleading when comparing them to other vaccines.
Covid-19 vaccines are great — but you still need to wear a mask for now|Umair Irfan|February 9, 2021|Vox
That could pose a problem even for vaccinated adults, says Mobeen Rathore, an infectious disease specialist and epidemiologist at the University of Florida College of Medicine.
Why aren’t kids getting vaccinated?|Niall Firth|February 8, 2021|MIT Technology Review
As we learn how to address current and future pandemics, it is worth understanding what we learned from the great infectious disease fights of the past.
Smallpox used to kill millions of people every year. Here’s how humans beat it.|Kelsey Piper|February 5, 2021|Vox

That’s especially true now as new, more infectious coronavirus variants await — putting us at risk of an even bigger surge than the one we saw during the holiday season if we ease up.
The case for optimism on Covid-19, in 2 charts|German Lopez|February 5, 2021|Vox
For most infectious, the amount is 100 or even 1,000 times that.
A Doctor Explains Why Cruise Ships Should Be Banned|Kent Sepkowitz|November 19, 2014|DAILY BEAST
Although bats may have creeped us out for centuries, their links to emerging infectious diseases are much more recent.
Bats’ Link to Ebola Finally Solved|Carrie Arnold|November 12, 2014|DAILY BEAST
In Malaysia and Bangladesh, a devastating infectious neurological disease emerged just a few years after Hendra.
Bats’ Link to Ebola Finally Solved|Carrie Arnold|November 12, 2014|DAILY BEAST
The only existing study, printed in the Journal of Infectious Diseases in 1999, leaves scientists with the same questions.
Blood Is Ebola’s Weapon and Weakness|Abby Haglage|October 26, 2014|DAILY BEAST
Adam Lausing, an infectious disease researcher at the University of Michigan, emphasized that Ebola is not a respiratory disease.
Fact-Checking the Sunday Shows: October 19|PunditFact.com|October 19, 2014|DAILY BEAST
The last movement had the infectious gayety that Mozart's things often have, with a magnificent cadenza by himself.
Music-Study in Germany|Amy Fay
The infectious diseases in which leukocytosis is absent (p. 160) often cause a slight decrease of leukocytes.
A Manual of Clinical Diagnosis|James Campbell Todd
(b) Acute infectious diseases, especially rheumatism and typhoid fever.
A Manual of Clinical Diagnosis|James Campbell Todd
Predominance of polymorphonuclear leukocytes (pus-corpuscles) points to an acute infectious process (Fig. 117).
A Manual of Clinical Diagnosis|James Campbell Todd
The usual cause of acute infectious conjunctivitis, especially in cities, seems to be the Koch-Weeks bacillus.
A Manual of Clinical Diagnosis|James Campbell Todd

British Dictionary definitions for infectious

infectious

/ (ɪnˈfɛkʃəs) /

adjective

(of a disease) capable of being transmittedCompare contagious

(of a disease) caused by microorganisms, such as bacteria, viruses, or protozoa

causing or transmitting infection

tending or apt to spread, as from one person to anotherinfectious mirth

international law

tainting or capable of tainting with illegality
rendering liable to seizure or forfeiture

Derived forms of infectious

infectiously, adverbinfectiousness, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for infectious

infectious

[ ĭn-fĕk′shəs ]

Capable of causing infection. See Note at contagious.

infectious

OTHER WORDS FOR infectious

Origin of infectious

synonym study for infectious

OTHER WORDS FROM infectious

WORDS THAT MAY BE CONFUSED WITH infectious

Words nearby infectious

Words related to infectious

How to use infectious in a sentence

British Dictionary definitions for infectious

Derived forms of infectious

Scientific definitions for infectious