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

The claimants allege pollution has been caused by run-off from farmland containing high concentrations of phosphorus, nitrogen and bacteria from the spreading of poultry manure and sewage bio solids used as fertiliser.

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But, at the moment, the MenB vaccine – the only protection against type B meningococcal bacteria, which makes up 90% of the meningitis cases in the UK – was only available to children.

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It's made up of a network of cells, tissues, and organs that work together to detect harmful invaders like viruses and bacteria, and help the body fight them off.

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When they compared healthy and infected animals, one group consistently stood out — the Vibrios, a type of bacteria commonly found in marine environments.

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The study measured odour levels against exposure time, and found that just 2–3 minutes of UVC treatment was sufficient to kill the bacteria and eliminate the foul smell.

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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.