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viruses

  • plural
    of virus.
    virus
    noun
    an ultramicroscopic (20 to 300 nanometers in diameter), metabolically inert, infectious agent that replicates only within the cells of living hosts, mainly bacteria, plants, and animals: composed of an RNA or DNA core, a protein coat, and, in more complex types, a surrounding envelope.

Example Sentences

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Type I interferons are signaling proteins that help alert cells when an infection is developing and form an important part of the body's early defenses against viruses and other pathogens.

From Science Daily ● Oct. 8, 2026

More patients, including children, have been arriving at A&E departments with flu and other respiratory viruses.

From BBC ● Oct. 8, 2026

He goes on to emphasize that what Claude found — a previously uncharacterized enzyme system found in viruses that infect bacteria — isn’t necessarily going to be useful.

From Salon ● Sep. 30, 2026

Some AI industry leaders fear doomsday scenarios such as the possibility of AI bots creating novel viruses capable of wiping out humanity.

From The Wall Street Journal ● Sep. 23, 2026

Like viruses, they simply take over the molecular machinery of a much larger, well-functioning cell and change it from a factory for making more cells into a factory for making more viroids.

From "Cosmos" by Carl Sagan