Infectious Meaning

/ɪnˈfɛk.ʃəs/
B2

Definition, CEFR level B2, pronunciation, examples, and quiz.

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adjCaused by an agent that enters the host's body (such as a bacterium, virus, parasite, or prion); often, also, transmitted among hosts via any of various routes (for example, contact, droplet-borne, airborne, waterborne, foodborne, fomite-borne, or bloodborne).

adjAble to infect others; capable of transmitting pathogens.

The infectious case was isolated from other patients.
Mumps is an infectious disease.
Antonyms:
None
CEFR Practice Quiz
The ____ virus quickly spread through the school, making many students sick.
CEFR Practice Quiz (Alternate)
The young girl has a very ____ laugh that soon had everyone in the room laughing along.

Borrowed from New Latin īnfectiōsus. By surface analysis, infect + -ious.

"I doubt that [saliva] is very infectious ... I don't think this is a normal route of transmission." — 1981 December 1, Sue Hyde, quoting Paul Black, “AIDS Update: Little To Cheer About”, in Gay Community News, volume 12, number 20, page 3:
"When Maisie first met Danny, she remembers that he had an infectious laugh and a love for music." — 2024 November 20, Fortesa Latifi, “How These Men Left the Manosphere — and Why Some May Never”, in Teen Vogue:

Explore More B2 Vocabulary Words

CEFR Practice Quiz
The ____ virus quickly spread through the school, making many students sick.
CEFR Practice Quiz (Alternate)
The young girl has a very ____ laugh that soon had everyone in the room laughing along.

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