bacteria

¹

[bak-teer-ee-uh]

plural noun

Microbiology.

singular

bacterium 

1. ubiquitous one-celled organisms, spherical, spiral, or rod-shaped and appearing singly or in chains, comprising numerous and variously classified phyla: among the inestimable number of species are those involved in fermentation, putrefaction, infectious diseases, and nitrogen fixation.

Bacteria

²

[bak-teer-ee-uh]

noun

(used with a singular or plural verb)

1. (in the three-domain system of classification) the taxonomic domain comprising the bacteria.

bacteria

/ bækˈtɪərɪə /

plural noun

1. a very large group of microorganisms comprising one of the three domains of living organisms. They are prokaryotic, unicellular, and either free-living in soil or water or parasites of plants or animals See also prokaryote

bacteria

1. sing. bacterium Microorganisms made up of a single cell that has no distinct nucleus. Bacteria reproduce by fission or by forming spores.

Some bacteria are beneficial to humans (for example, those that live in the stomach and aid digestion), and some are harmful (for example, those that cause disease).

Other Word Forms

• bacterial adjective
• bacterially adverb
• nonbacterial adjective
• nonbacterially adverb

Word History and Origins

Origin of bacteria¹

First recorded in 1860–65; from New Latin, from Greek baktḗria, plural of baktḗrion, diminutive of baktēría “staff, cane”; bacterium

Origin of bacteria²

First recorded in 1860–65; from New Latin; bacteria ( def. )

Word History and Origins

Origin of bacteria¹

C19: plural of New Latin bacterium , from Greek baktērion , literally: a little stick, from baktron rod, staff

Example Sentences

"Viruses can be transmitted, and bacteria as well, by air conditioning systems because they cool air. That means you get condensation and you get water build-up unless the air conditioning system is well maintained."

From BBC

“Nobody knows what the health effects are of breathing that level of hydrogen sulfide gas, plus the viruses, plus the bacteria, plus all the other chemicals that we’ve detected,” Prather said.

From Los Angeles Times

Earlier in 2021, an independent review found 84 children were infected with rare bacteria while undergoing treatment, with a third suffering a severe health impact.

From BBC

It was estimated their loss led to half a million deaths over five years due to the spread of disease and bacteria the vultures would have removed from the environment.

From BBC

“If the infection is overwhelming,” he said, “then the bacteria can spread fairly quickly into the bloodstream, and then it becomes very dangerous.”

From Los Angeles Times

When To Use

Plural word for bacteria

Bacteria is the plural form of the singular bacterium. Because microscopic bacterium is most often found in multiples, the plural form bacteria is more commonly used. The plurals of several other singular words ending in -um are also formed this way, such as memorandum/memoranda and curriculum/curricula.The irregular noun bacterium’s plural derives directly from its original pluralization in Latin and Greek. Bacteria is sometimes treated as a singular collective noun. However, this is not standard in English, and bacteria should be treated as a plural form.