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
An antibiotic to knock out the overgrowth should do the trick, right? Erica Sloan, SELF, 24 Oct. 2024 Get prompt treatment for any infections, and always finish the antibiotics that you’re prescribed. Kelly Burch Published, Verywell Health, 24 Oct. 2024
Adjective
Possible causes include high-stress levels, a diet rich in sugary or processed foods, not enough sleep, and frequent antibiotic prescriptions. Robert Burakoff, Verywell Health, 24 Oct. 2024 Indeed, 45% of people who take an antibiotic course for SIBO experience a recurrence of their symptoms. Erica Sloan, SELF, 24 Oct. 2024 See all Example Sentences for antibiotic 

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 4 Nov. 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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