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

Other Words from antibiotic

Adjective

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

Examples of antibiotic in a Sentence

Recent Examples on the Web: Noun Arsphenamine, which is generally considered to be the first synthetic antibiotic, was discovered and used in treatment in 1907 by a German physician Paul Erlich. John Drake, Forbes, 11 Nov. 2021 My doctor has given me a standing order for urinalysis and culture to determine the infection, and prescriptions for an antibiotic to start when needed until the proper source is found. Dr. Keith Roach, oregonlive, 20 Oct. 2021 So, the novel antibiotic is not reaching patients who need it. Michelle Mcmurry-heath And Henry Skinner, Fortune, 25 Nov. 2021 Life-threatening infection led to the removal of a kidney and his treatment with what was then an experimental antibiotic, streptomycin, initially used to treat tuberculosis. Washington Post, 5 Dec. 2021 But this custom antibiotic wasn’t entirely his own recipe. Max G. Levy, Wired, 30 Nov. 2021 My journey began with a prescription for the standard, first-choice antibiotic for UTIs: nitrofurantoin. Natalie Ma, STAT, 31 Oct. 2021 His family physician gave him an antibiotic that didn’t work and ordered a chest X-ray in April 2016. Maggie Menderski, The Courier-Journal, 22 Nov. 2021 A few weeks ago, Amanda Powers dropped off a prescription for an antibiotic for her husband at 9:30 a.m. Shari Rudavsky, The Indianapolis Star, 22 Oct. 2021 Recent Examples on the Web: Adjective According to the website, birds are free-range, fed a vegetarian diet, are antibiotic free, and air chilled. Sheryl Julian, BostonGlobe.com, 7 Dec. 2021 Each pouch contains bite-sized chunks of antibiotic-free chicken packed with a craveable spicy-sweet flavor for a snack that’s high in protein, big on flavor, and kinder to the planet. Katie Chang, Forbes, 20 Sep. 2021 The meat is sourced from farmer Russ Kremer, who raises the antibiotic-free pigs on small family farms in the Missouri Ozarks. Jeremy Repanich, Robb Report, 19 July 2021 Meredith Bell, owner of Autonomy Farms in Bakersfield, specializes in hormone- and antibiotic-free meat and eggs. Los Angeles Times, 19 Mar. 2021 The last push came during the Obama administration, but citing the need for more data, the USDA rejected a proposal to ban certain antibiotic-resistant strains. Bernice Yeung, ProPublica, 29 Oct. 2021 Bacharach related an anecdote about his son Oliver, who was hospitalized with an antibiotic-resistant staph infection. The New Yorker, 25 Oct. 2021 Meanwhile, the Orinoco crocodile is important to Indigenous South Americans who harvest the eggs for food, as well as to medical research where the reptile’s blood has been found to contain antibiotic and anti-cancer properties. Sheryl Devore, chicagotribune.com, 24 Nov. 2021 One such project is seeking to discover the next generation of antibiotics, in order to counter antibiotic resistance. New York Times, 24 Nov. 2021

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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Dictionary Entries Near antibiotic

antibiosis

antibiotic

antiblack

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Statistics for antibiotic

Last Updated

19 Jan 2022

Cite this Entry

“Antibiotic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/antibiotic. Accessed 20 Jan. 2022.

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More Definitions for antibiotic

antibiotic

noun

English Language Learners Definition of antibiotic

: 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 antibiotic (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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