bacterial

adjective

bac·​te·​ri·​al bak-ˈtir-ē-əl How to pronounce bacterial (audio)
: of, relating to, or caused by bacteria
bacterial infection
bacterially
bak-ˈtir-ē-ə-lē How to pronounce bacterial (audio)
adverb

Examples of bacterial in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The palace said he was being treated for a bacterial infection in his blood. — Terje Solsvik, USA Today, 28 Aug. 2026 Siegel noted that measles weakens the immune system and increases the risk of pneumonia, which can stem from measles itself or from a secondary bacterial infection. — Melissa Rudy, FOXNews.com, 28 Aug. 2026 This bacterial infection sometimes comes back after a short course of antibiotics, but that’s not because of resistant bacteria. — Amy J. Mathers, The Conversation, 28 Aug. 2026 Researchers have managed to add some new amino acids to a bacterial cell and were able to make proteins that were one amino acid less than usual. — ArsTechnica, 26 Aug. 2026 See All Example Sentences for bacterial

Word History

First Known Use

1869, in the meaning defined above

Time Traveler
The first known use of bacterial was in 1869

Phrases Containing bacterial

Rhymes for bacterial

See All Rhymes for bacterial

Browse Nearby Words

bacteriacide
bacterial
bacterial blight
See all Nearby Words

Cite this Entry

“Bacterial.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bacterial. Accessed 1 Sep. 2026.

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Kids Definition

bacterial

adjective
bac·​te·​ri·​al bak-ˈtir-ē-əl How to pronounce bacterial (audio)
: of, relating to, or caused by bacteria

Medical Definition

bacterial

adjective
bac·​te·​ri·​al bak-ˈtir-ē-əl How to pronounce bacterial (audio)
: of, relating to, or caused by bacteria
a bacterial chromosome
bacterial infection
bacterial endocarditis
bacterially
-ə-lē How to pronounce bacterial (audio)
adverb
Last Updated: - Updated example sentences
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