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Showing results for infectious. Search instead for infectiousl.
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

Nacua became known for his infectious enthusiasm and ability to catch almost anything Rams MVP quarterback Matthew Stafford threw his way.

From Los Angeles Times • Apr. 2, 2026

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

From Science Daily • Mar. 17, 2026

While it is not as infectious as illnesses like flu or Covid, it can take a turn for the worse "really quickly", he added.

From BBC • Mar. 17, 2026

Indeed, if laboratory mice have too much HLA diversity, Black told me, researchers can’t use them to observe the progress of an infectious disease.

From "1491" by Charles C. Mann