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

From Flesh-Eating Bacteria After Fishing with His Son Billiris is still in the hospital, where doctors gave him antibiotics to kill off the infection, and doing better. Julie Mazziotta, PEOPLE.com, "Florida Boat Captain Hospitalized After Contracting Flesh-Eating Bacteria: ‘Now I’m More Aware’," 2 Aug. 2019 After Deja was given antibiotics, she was placed in the intensive care unit and diagnosed with pneumococcal meningitis, which is an infection of the membranes covering the brain and spinal cord. al.com, "‘Her strength was amazing’: After daughter’s death, Alabama mother continues her legacy through charity," 18 July 2019 She was given antibiotics, but her condition deteriorated further. Bill Lambrecht, ExpressNews.com, "House opens inquiry into treatment of children at migrant detention facilities," 10 July 2019 Its economy has collapsed, plagued with shortages of everything from toilet paper to antibiotics to food. Washington Post, "The Standoff in Venezuela, Explained," 18 Sep. 2019 No longer could phenotypic heterogeneity be shrugged off as a quirk of the bacterial response to antibiotics. Quanta Magazine, "Bacterial Clones Show Surprising Individuality," 4 Sep. 2019 But the patients’ failure to respond to antibiotics led the doctors to believe they had been harmed by a toxic substance. Sheila Kaplan, BostonGlobe.com, "Dozens of young people sickened after vaping; physicians are stumped," 15 Aug. 2019 Here’s an important reason why: Just like bacteria can evolve resistance to antibiotics, roaches can evolve resistance to insecticides. Brian Resnick, Vox, "One big reason you can’t get rid of cockroaches," 3 July 2019 It’s also theoretically possible to get methicillin-resistant Staphylococcus aureus (MRSA), which is basically a staph infection that’s resistant to antibiotics, the CDC explains. Patia Braithwaite, SELF, "Yes, You Really Should Wear Shower Shoes in the Gym Locker Room," 12 June 2019

Recent Examples on the Web: Adjective

Initially, scientists thought that persisters might come from a genetically distinctive subpopulation that grew more slowly even before the antibiotic treatments. Quanta Magazine, "Bacterial Clones Show Surprising Individuality," 4 Sep. 2019 And the bacterial bits included a few genes for antibiotic resistance commonly found in plasmids. Megan Molteni, WIRED, "Brazil's Plans for Gene-Edited Cows Got Scrapped—Here's Why," 26 Aug. 2019 Each year, at least 2 million people in the United States get an antibiotic-resistant infection, and at least 23,000 people die, a CDC report found. N'dea Yancey-bragg, USA TODAY, "FDA issues warning after patient dies from fecal transplant containing drug-resistant bacteria," 13 June 2019 At the same time, some common STIs, such as gonorrhea and shigellosis, are becoming harder to treat because of antibiotic resistance. Jason Gale | Bloomberg, Washington Post, "Why Sex-Related Infections Are Spreading Again: QuickTake," 7 June 2019 Other possible factors in celiac disease still need to be considered, such as early childhood infections, changes in gut bacteria, and antibiotic exposure, noted Dr. Jacqueline Jossen. Dennis Thompson, baltimoresun.com, "Lots of gluten during toddler years might raise odds for celiac disease," 11 Sep. 2019 Another potential nit: Researchers found antibiotic residues in fruit that were more than three times higher than are permissible, a potential hurdle for injecting antibiotics into citrus trees. Andrew Jacobs, New York Times, "Spraying Antibiotics to Fight Citrus Scourge Doesn’t Help, Study Finds," 16 Aug. 2019 Of those who live long enough to seek treatment—an arduous regimen requiring patients to undergo antibiotic injections and take up to 40 pills daily for as long as two years—just 34 percent are ultimately cured. Meilan Solly, Smithsonian, "F.D.A. Approves New Treatment for Deadliest Strain of Tuberculosis," 15 Aug. 2019 The company is quick to point out that its salmon are antibiotic free. Los Angeles Times, "Data rigging is latest Chile salmon farm scandal," 4 Aug. 2019

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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Statistics for antibiotic

Last Updated

14 Oct 2019

Look-up Popularity

Time Traveler for antibiotic

The first known use of antibiotic was in 1891

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More Definitions for antibiotic

antibiotic

noun

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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Comments on antibiotic

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