Escherichia coli (E. coli) is a type of bacteria that normally lives in the intestines of people and animals. It is a facultative anaerobe, meaning it can survive with or without oxygen.

Here's a breakdown of the meaning:

* Escherichia: The genus name, honoring German pediatrician Theodor Escherich, who first described the bacterium in 1885.

* Coli: Refers to the colon, the large intestine where the bacterium is typically found.

Significance:

* Beneficial role: Most strains of E. coli are harmless and even beneficial, aiding in digestion and producing vitamins.

* Pathogenic strains: However, some strains can cause serious infections, such as urinary tract infections (UTIs), diarrhea, and food poisoning.

* Indicator organism: The presence of certain E. coli strains in water or food indicates potential fecal contamination and health risks.

In summary, Escherichia coli is a bacterium that is a normal inhabitant of the human gut, but some strains can cause disease.