antibiotic

noun
an·​ti·​bi·​ot·​ic | \ ˌan-tē-bī-ˈä-tik, -ˌtī- How to pronounce antibiotic (audio) ; -bē-ˈä- How to pronounce antibiotic (audio) \

Definition of antibiotic

 (Entry 1 of 2)

: a substance able to inhibit or kill microorganisms specifically : an antibacterial substance (such as penicillin, cephalosporin, and ciprofloxacin) that is used to treat or prevent infections by killing or inhibiting the growth of bacteria in or on the body, that is administered orally, topically, or by injection, and that is isolated from cultures of certain microorganisms (such as fungi) or is of semi-synthetic or synthetic origin Symptoms of campylobacteriosis include muscle aches, fever, cramps and diarrhea leading to gastrointestinal illness, which can be treated with antibiotics. Chicago Daily Herald Another way to produce new variants of established antibiotics is to use genetic engineering to alter the biochemical pathways of the microbes that produce them. New Scientist Experts agree that by spiking animal feed with antibiotics, conventional farmers are speeding the emergence of drug-resistant bacteria. — Geoffrey Cowley

Note: While antibiotics are effective mainly against bacteria, they are sometimes used to treat protozoal infections. Some consider antibiotics to include only those derived fully or partly from microorganisms and exclude synthetic forms from this class of drugs.

antibiotic

adjective

Definition of antibiotic (Entry 2 of 2)

1 : tending to prevent, inhibit, or destroy life
2 : of or relating to antibiotics or to antibiosis antibiotic drugs

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Other Words from antibiotic

Adjective

antibiotically \ ˌan-​tē-​bī-​ˈä-​ti-​k(ə-​)lē , ˌan-​ˌtī-​ How to pronounce antibiotically (audio) ; -​bē-​ˈä-​ \ adverb

Examples of antibiotic in a Sentence

Recent Examples on the Web: Noun The researchers don’t yet know whether the presence of antibiotic-producing bacteria in the woodrat nests is what keeps pathogens out. Stephenie Livingston, Science | AAAS, "Florida woodrat nests are laced with antibiotic-producing bacteria," 15 Sep. 2020 That means measure by hand, with a ruler, how close bacteria grow to an antibiotic on a paper disc. Emma Court, Bloomberg.com, "U.S. Medical Supply Shortage Plaguing More Than Just Tests for Covid-19," 1 Sep. 2020 In 2017, he was doused with a green antibiotic that compromised his vision. Regina Smyth, The Conversation, "How Alexei Navalny revolutionized opposition politics in Russia, before his apparent poisoning," 21 Aug. 2020 The study continued for 40 years with the men not getting proper treatment, even after penicillin proved to be a viable antibiotic in 1947. Richard Newby, The Hollywood Reporter, "'Project Power' and a Summer Without Superheroes," 15 Aug. 2020 On the surface, the use of Zithromax seems superfluous since an antibiotic is used to fight bacteria, not a virus. David Hogberg, Washington Examiner, "Disconnect between FDA and doctors prescribing hydroxychloroquine," 3 Aug. 2020 Of 100 candidate molecules selected by the system for further analysis, one proved to be a potent new antibiotic. The Economist, "Artificial intelligence and its limits An understanding of AI’s limitations is starting to sink in," 11 June 2020 Another team of scientists at the HonorHealth Research Institute in Arizona is actively recruiting participants for a clinical trial involving the use of atovaquone in combination with azithromycin, an antibiotic, to treat COVID-19. Dallas News, "UT Southwestern scientists investigate pneumonia drug as possible COVID-19 treatment," 1 July 2020 Mass-producing the antibiotic became as much of a national-security priority as building an atom bomb. The Economist, "Schumpeter The quest for a vaccine could restore faith in big pharma," 6 June 2020 Recent Examples on the Web: Adjective Several forces during the pandemic may lead to a surge in antibiotic use. Jowa (zhuo) Shi And Ateev Mehrotra, STAT, "Inappropriately prescribed antibiotics will likely accompany the winter surge of Covid-19," 9 Nov. 2020 Fewer than 10% of people with brucellosis have a relapse of the disease following antibiotic treatment. Claire Gillespie, Health.com, "A Brucellosis Outbreak in China Has Been Linked to a Factory Leak—Here's What You Need to Know," 18 Sep. 2020 And its impact could last beyond the current pandemic: Similar systems could be used to track drug use, antibiotic resistance, toxic pollutants, and outbreaks of other infectious diseases. Katherine Ellen Foley, Quartz, "Old sewers are becoming a modern Covid-19 watchdog," 29 Oct. 2020 The study finds that outpatients with the coronavirus who were treated with hydroxychloroquine combined with zinc and the antibiotic azithromycin were less likely to be hospitalized. David Hogberg, Washington Examiner, "Study shows hydroxychloroquine may be effective for outpatients with COVID-19," 27 Oct. 2020 Urban air pollution was driving energy consumption, leading to even greater levels of air pollution, which in turn was driving antibiotic resistance. Rafil Kroll-zaidi, Harper's Magazine, "Findings," 27 Oct. 2020 Bacterial species are arrayed in a circular layout, with three bars for each bacterial infection representing the amount of each antibiotic needed to treat it. Andrew Gelman, Wired, "Is Your Chart a Detective Story? Or a Police Report?," 25 Aug. 2020 The team used the genetic information to compare Fleming's mold with two strains of Penicillium from the United States that are used to produce the antibiotic on an industrial scale. Katie Hunt, CNN, "Scientists sequence the 92-year-old mold that produced the first antibiotic, penicillin," 24 Sep. 2020 This could be a topical antibiotic ointment or an acne spot treatment. Rebecca Dancer, Seventeen, "So, You Picked a Zit—Now What?," 8 July 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'antibiotic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of antibiotic

Noun

1943, in the meaning defined above

Adjective

1891, in the meaning defined at sense 1

History and Etymology for antibiotic

Noun

derivative of antibiotic entry 2

Note: Noun use of the adjective antibiotic probably began in the early 1940's, preceded by the frequent collocation antibiotic substance, but was not common before Selman Waksman's paper "What Is an Antibiotic or an Antibiotic Substance?" (Mycologia, vol. 39, no. 5 [September-October, 1947]). Waksman has been credited with coining antibiotic, though he does not claim to have done so, and in fact gives an account of the earlier history of the word in this article.

Adjective

borrowed from French antibiotique, derivative of antibiose antibiosis (after symbiose symbiosis : symbiotique symbiotic)

Note: See note at antibiosis.

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Time Traveler for antibiotic

Time Traveler

The first known use of antibiotic was in 1891

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Statistics for antibiotic

Cite this Entry

“Antibiotic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/antibiotic. Accessed 3 Dec. 2020.

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More Definitions for antibiotic

antibiotic

noun
How to pronounce antibiotic (audio) How to pronounce antibiotic (audio)

English Language Learners Definition of antibiotic

medical : a drug that is used to kill harmful bacteria and to cure infections

antibiotic

noun
an·​ti·​bi·​ot·​ic | \ ˌan-ti-bī-ˈä-tik How to pronounce antibiotic (audio) \

Kids Definition of antibiotic

: a substance produced by living things and especially by bacteria and fungi that is used to kill or prevent the growth of harmful germs

antibiotic

adjective
an·​ti·​bi·​ot·​ic | \ -bī-ˈät-ik; -bē- How to pronounce antibiotic (audio) \

Medical Definition of antibiotic

 (Entry 1 of 2)

1 : tending to prevent, inhibit, or destroy life
2 : of or relating to antibiotics or to antibiosis

Other Words from antibiotic

antibiotically \ -​i-​k(ə-​)lē How to pronounce antibiotically (audio) \ adverb

antibiotic

noun

Medical Definition of antibiotic (Entry 2 of 2)

: a substance able to inhibit or kill microorganisms specifically an antibacterial substance (as penicillin, cephalosporin, and ciprofloxacin) that is used to treat or prevent infections by killing or inhibiting the growth of bacteria in or on the body, that is administered orally, topically, or by injection, and that is isolated from cultures of certain microorganisms (as fungi) or is of semi-synthetic or synthetic origin

Note: While antibiotics are effective mainly against bacteria, they are sometimes used to treat protozoal infections. Some consider antibiotics to include only those derived fully or partly from microorganisms and exclude synthetic forms from this class of drugs.

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