E. coli
noun
plural E. coli
: an enterobacterium (Escherichia coli) that is used in public health as an indicator of fecal pollution (as of water or food) and in medicine and genetics as a research organism and that occurs in various strains that may live as harmless inhabitants of the human lower intestine or may produce a toxin causing intestinal illness see enterobacterium illustration
Examples of E. coli in a Sentence
Recent Examples on the Web
The collapse led to a spike in E. coli in the surrounding area, which DC Water initially underestimated by a sweeping margin.
—
Emily Hallas, The Washington Examiner, 21 Feb. 2026
Responders should wear personal protective equipment during those calls due to the dangerous levels of E. coli and other contaminants in the water.
—Isabelle Schmeler, NBC news, 18 Feb. 2026
The spill has prompted widespread public health concerns as E. coli bacteria have been detected at dangerous levels in parts of the river, and the leakage underscores the risks posed by aging sewer infrastructure.
—Kathryn Palmer, USA Today, 18 Feb. 2026
Government and independent researchers have monitored the quality of the water at and downstream from the rupture, testing for E. coli bacteria.
—Ryan Mancini, The Hill, 17 Feb. 2026
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Emily Hallas, The Washington Examiner, 21 Feb. 2026
Responders should wear personal protective equipment during those calls due to the dangerous levels of E. coli and other contaminants in the water.
—Isabelle Schmeler, NBC news, 18 Feb. 2026
The spill has prompted widespread public health concerns as E. coli bacteria have been detected at dangerous levels in parts of the river, and the leakage underscores the risks posed by aging sewer infrastructure.
—Kathryn Palmer, USA Today, 18 Feb. 2026
Government and independent researchers have monitored the quality of the water at and downstream from the rupture, testing for E. coli bacteria.
—Ryan Mancini, The Hill, 17 Feb. 2026
See All Example Sentences for E. coli
Cite this Entry
“E. coli.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/E.%20coli. Accessed 1 Mar. 2026.
Copy CitationKids Definition
E. coli
noun
plural E. coli
: a bacterium in the shape of a short rod that may cause intestinal illness
Etymology
short for Escherichia coli, the taxonomic name in biology
Medical Definition
E. coli
nounˌē-ˈkō-ˌlī
plural E. coli also E. colis
: a straight rod-shaped gram-negative bacterium (Escherichia coli of the family Enterobacteriaceae) that is used in public health as an indicator of fecal pollution (as of water or food) and in medicine and genetics as a research organism and that occurs in various strains that may live as harmless inhabitants of the human lower intestine or may produce a toxin causing intestinal illness marked especially by diarrhea
one million acid-resistant E. coli per gram of feces—John Schwartz
John Schwartzthis E. coli can survive … longer than all the other E. colis—Ed Geldreich
Ed GeldreichLove words? Need even more definitions?
Merriam-Webster unabridged
