phage

1 of 2

noun

ˈfāj 

also

ˈfäzh 

plural phages also phage

: a virus that infects bacteria : bacteriophage

They cloned the antibody genes and inserted them into phage, a virus that infects bacteria cells.

—Teresa L. White

Bacteriophages, also known simply as phages, came to light around 90 years ago, when two European scientists independently discovered that there are viruses that kill bacteria.

—John Travis

-phage

2 of 2

noun combining form

: virus or cell that destroys cells

bacteriophage

microphage

Examples of phage in a Sentence

Recent Examples on the Web

Noun

The founders came to understand that dermatologists are among the top prescribers of antibiotics across the healthcare sector and that phage therapy could be a viable solution. —Jason Phillips, USA Today, 4 June 2025

Each person’s gut may harbor hundreds or even a thousand species of phages. —Carl Zimmer, New York Times, 19 Feb. 2025

The company’s novel approach to phage therapy, powered by microbial genomics, is already transforming dermatology — and that’s just the beginning. —WWD, 14 Feb. 2025

Bacteria can develop resistance to a phage that preys on it, but because of evolution, the phage can also evolve more mechanisms to attach to the bugs. —Saima S. Iqbal, Scientific American, 31 Dec. 2024

Word History

Etymology

Noun

by shortening

Noun combining form

Greek -phagos one that eats, from -phagos -phagous

First Known Use

Noun

1920, in the meaning defined above

Rhymes for phage

• age
• gauge
• phage
• plage
• rage
• stage
• wage
• alienage
• assuage
• backstage
• bocage
• downstage

Kids Definition

phage

noun

ˈfāj 

 also  ˈfäzh

: bacteriophage

Medical Definition

phage

noun

ˈfāj 

also

ˈfäzh 

plural phages also phage

: a virus that infects bacteria : bacteriophage

To infect a host bacterium, a phage will first interact with receptors on the host cell, adsorb and then inject its genome.

—George P. C. Salmond and Peter C. Fineran, Nature Reviews Microbiology

Phages have various possible life cycles which, along with interaction with their physical environment, dictate their role in bacterial/archaeal biology.

—Martha R. J. Clokie et al., Bacteriophage