Science Word Wednesday: Bacteriophage

Sep 09, 2020
By Nicole Gadda


(Noun. /bak-TEE-ree-o-faj/)

A bacteriophage is a virus that only infects bacteria. Like all viruses, they’re not living organisms and need a host to survive. Scientists estimate that there are over 1031 individual bacteriophages on Earth, meaning they outnumber all living organisms combined!

A bacteriophage is made up of 3 major parts: a capsid that houses DNA (blue), a tail used to infect bacterial cells (yellow), and tail fibers that help the bacteriophage attach to bacterial cells (pink).

How do I use it in a sentence:

“Dr. Green is studying how bacteriophages attack infectious bacterial cells. She wants to develop a way to use bacteriophages as an alternative to antibiotics to treat bacterial infections.”

Etymology & history of usage:

The term “bacteriophage” literally means “bacteria eater.” It comes from the Greek word φαγεῖν (phagein), which means “to devour.” This was coined by Felix d’Herelle after he discovered bacteriophages in 1917.

Related terms:

Prophage, lysogeny, plasmid, phage therapy

Fields of study in which this word is commonly used:

Microbiology, biotechnology, genetics

Edited by Emma Goldberg and Anna Wheless