bacteriophage

American  

[bak-teer-ee-uh-feyj] / bækˈtɪər i əˌfeɪdʒ /

noun

1. any of a group of viruses that infect specific bacteria, usually causing their disintegration or dissolution.

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bacteriophage British  

/ bækˌtɪərɪˈɒfəɡəs, bækˈtɪərɪəˌfeɪdʒ, bækˌtɪərɪəˈfædʒɪk /

noun

1. Often shortened to: phage.  a virus that is parasitic in a bacterium and multiplies within its host, which is destroyed when the new viruses are released

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bacteriophage Scientific  

/ băk-tîr′ē-ə-fāj′ /

1. A virus that infects and destroys bacterial cells.

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Other Word Forms

• bacteriophagic adjective
• bacteriophagous adjective
• bacteriophagy noun

Etymology

Origin of bacteriophage

First recorded in 1920–25; from French bactériophage; bacterio-, -phage

Example Sentences

The researchers also discovered that elements of their active genetic system can be transported by bacteriophage, or phage, viruses that naturally infect bacteria.

From Science Daily • Feb. 18, 2026

They're known as bacteria eaters, or bacteriophage, or commonly as phage.

From BBC • Jun. 27, 2025

Unlike commercial antibiotics, phages evolve alongside their bacterial hosts, dodging and parrying the bacterial response so that for every pathogen, there’s likely a bacteriophage, somewhere, that eats it.

From Salon • Nov. 20, 2024

In our recent work, my collaborators and I describe a satellite bacteriophage completely unlike previously known satellites, one that has evolved a unique, spooky lifestyle.

From Salon • Nov. 9, 2023

The toxins of diphtheria bacilli and streptococci are produced when the organisms have been infected by bacteriophage; it is the virus that provides the code for toxin.

From "The Lives of a Cell" by Lewis Thomas