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Showing results for infectious. Search instead for infectiousn.
Definitions

infectious

[in-fek-shuhs] / ɪnˈfɛk ʃəs /
ADJECTIVE
catching, spreading
Synonyms
STRONGEST
contagious toxic virulent
WEAK
communicable contaminating corrupting defiling diseased epidemic infective mephitic miasmic noxious pestilent pestilential poisoning polluting transferable transmittable vitiating
Antonyms
STRONGEST
harmless nonpoisonous
WEAK
antiseptic germless non-infectious uncommunicable uncontagious

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Dr. Amesh Adalja, an infectious disease expert and senior scholar at Johns Hopkins Center for Health Security, told Salon he is not hopeful the outbreaks can be contained at this point.

From Salon • Apr. 8, 2026

After hours cooling his heels, Kornev is then informed that Stepniak is ill with an infectious disease — come back another time.

From Los Angeles Times • Mar. 26, 2026

Bellamy's rambunctious and infectious approach to his playing career made him one of the Premier League's most effective forwards.

From BBC • Mar. 24, 2026

Because of their strong impact, scientists began developing mRNA vaccines for other infectious diseases.

From Science Daily • Mar. 17, 2026

Her enthusiasm was infectious and I soon lost myself in the excitement of the moment, ignoring my original reasons for wanting to explore the tunnels.

From "The Name of the Wind" by Patrick Rothfuss