antibiotic

1 of 2

noun

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

2 of 2

adjective

1
: tending to prevent, inhibit, or destroy life
2
: of or relating to antibiotics or to antibiosis
antibiotic drugs
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
And researchers have long been puzzled by a medical mystery: Some women susceptible to recurrent UTIs experience symptoms without any signs of bacteria, or after an infection has supposedly been cleared with antibiotics. Theresa Gaffney, STAT, 1 Mar. 2024 The individual is reported to be in early stages of the illness, and the patient and close contacts are being treated with antibiotics. Katia Hetter, CNN, 29 Feb. 2024 Bacterial infections in humans, pets, and livestock are often treated with antibiotics, but that’s an option for wild deer for obvious reasons. Katie Hill, Outdoor Life, 29 Feb. 2024 Most listeria infections can be treated with antibiotics. Alex Groth, Journal Sentinel, 26 Feb. 2024 Meningococcal disease can be treated with antibiotics if detected in time and is preventable through vaccination, the department said in its release. The Enquirer, 23 Feb. 2024 Additional antibiotics are added in cases of meningitis, due to the challenge of getting drugs into the central nervous system at high enough levels to be effective. Mark Kortepeter, Forbes, 14 Feb. 2024 All forms of plague are treatable with common antibiotics, and people who seek treatment early have a better chance of a full recovery, according to the CDC.Am I at risk of plague? Rebecca Boone, Fortune Well, 13 Feb. 2024 Fawcett said doctors gave antibiotics to the patient's close contacts out of an abundance of caution to prevent any potential infections from developing into symptoms. Aria Bendix, NBC News, 9 Feb. 2024
Adjective
If your symptoms don’t go away or get worse after a week or two, make an appointment with a dermatologist or your primary care provider, in case an infection is to blame (which may require an antibiotic or antifungal medication). Krissy Brady, SELF, 5 Mar. 2024 Also good for those just getting started on a probiotic, as the single strain targets gut health, especially after antibiotic use. Shushy Rita Setrakian Ms, Verywell Health, 21 Feb. 2024 With heavy antibiotic use, bacteria evolve to thwart their effects. Emily Mullin, WIRED, 14 Feb. 2024 Her doctors were running out of antibiotic options for Woerner, who is prone to sinus infections. Erika Edwards, NBC News, 14 Dec. 2023 When an antibiotic attempts to bind to the ribosome, that methyl group repels it. Corinne Purtill, Los Angeles Times, 15 Feb. 2024 The man’s symptoms began in mid-September with a painful red lesion near his shoulder that failed to respond to antibiotic treatment. Tribune News Service, The Mercury News, 14 Feb. 2024 Listeria is generally treated with the common antibiotic ampicillin. Mark Kortepeter, Forbes, 14 Feb. 2024 That medication is an oral antibiotic, Nirmatrelvir, which goes by the brand name Paxlovid. Margie Zable Fisher, Fortune Well, 5 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'antibiotic.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

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.

First Known Use

Noun

1943, in the meaning defined above

Adjective

1891, in the meaning defined at sense 1

Time Traveler
The first known use of antibiotic was in 1891

Dictionary Entries Near antibiotic

Cite this Entry

“Antibiotic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/antibiotic. Accessed 19 Mar. 2024.

Kids Definition

antibiotic

noun
an·​ti·​bi·​ot·​ic
ˌant-i-bī-ˈät-ik,
ˌan-ˌtī-,
ˌant-i-bē-
: a substance produced by an organism (as a fungus or bacterium) that in dilute solution inhibits or kills a harmful microscopic plant or animal and especially one that causes disease
antibiotic adjective

Medical Definition

antibiotic

1 of 2 adjective
an·​ti·​bi·​ot·​ic -bī-ˈät-ik; -bē- How to pronounce antibiotic (audio)
1
: tending to prevent, inhibit, or destroy life
2
: of or relating to antibiotics or to antibiosis
antibiotically adverb

antibiotic

2 of 2 noun
: 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.

Last Updated: - Updated example sentences
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