from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A substance, such as penicillin or erythromycin, produced by or derived from certain microorganisms, including fungi and bacteria, that can destroy or inhibit the growth of other microorganisms, especially bacteria. Antibiotics are widely used in the prevention and treatment of infectious diseases.
  • adjective Of or relating to antibiotics.
  • adjective Of or relating to antibiosis.
  • adjective Destroying life or preventing the inception or continuance of life.

from The Century Dictionary.

  • Opposed to a belief in the presence or possibility of life.
  • In biology, injurious or deadly to the living substance: as, an antibiotic secretion.

from the GNU version of the Collaborative International Dictionary of English.

  • noun A chemical substance derived from a mold or bacterium that kills microorganisms and cures infections.
  • noun any chemical substance having therapeutically useful antibacterial or antifungal activity; -- used commonly but loosely for synthetic as well as natural antimicrobial agents.
  • adjective of or pertaining to an antibiotic.
  • adjective having antimicrobial activity; capable of killing microbes.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun pharmacology Any substance that can destroy or inhibit the growth of bacteria and similar microorganisms.
  • adjective pharmacology Of or relating to antibiotics.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a chemical substance derivable from a mold or bacterium that can kill microorganisms and cure bacterial infections
  • adjective of or relating to antibiotic drugs


from Wiktionary, Creative Commons Attribution/Share-Alike License

From French antibiotique, coined in 1889 by P. Vuillemin from anti- and biotique, from Ancient Greek βιωτικός (biōtikós, "concerning or relating to life") (from βίος (bíos, "life"), from Proto-Indo-European *gʷeih₃w- (“to live”)), perhaps influenced by ἀντίϐιος (antíbios, "opposed")


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  • The company's news, better than the market expected, was overshadowed by Smithfield's part in another story: The Russian Federation banned imports of pork from more U.S. plants because of what it called antibiotic contamination. - News Articles 2009

  • Perhaps the most well known antibiotic is penicillin.

    Vaccine Science 2010

  • When the antibiotic is found to have a fatal side effect, the company buries victims in a mass grave outside of town and kills others who know of the problem.

    Op-eds on vaccines by Paul Offit, MD 2010

  • The damned antibiotic is making me ill, which always happens, and always surprises me, regardless.

    "persnal magnacism and sex repeal" greygirlbeast 2008

  • So my antibiotic is exposed until I can take it in the morning.

    My boyfriend is so stupid Jerine 2008

  • So my antibiotic is exposed until I can take it in the morning.

    Archive 2008-10-01 Jerine 2008

  • The reason is that neither single nor double point mutations to the enzyme allowed it to destroy the certain antibiotic (called "imipenem").

    Behe's Test 2008

  • The reason I am told and Lyme doctors concur, that long term antibiotic use should be considered when Lyme disease is suspected is because of the following:

    Michealene Cristini Risley: Lyme disease-where is "House" when you need him? 2009

  • "They are commonly applied by insurance companies in restricting coverage for long-term antibiotic treatment or other medical care and also strongly influence physician treatment decisions."

    Michealene Cristini Risley: Lyme: Emerging Disease or Hidden Epidemic? 2009

  • Ironically, the antibiotic is to prevent problems that might crop up during chemo.

    Archive 2007-08-19 Bill Crider 2007


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  • I prefer -tee- for the second syllable of this word (and others beginning with the prefix anti-), and the evidence of my ears says this has been the dominant pronunciation in cultivated American speech for some time. The variant with short i as in fit (listen to the American Heritage Dictionary’s pronunciation) appears in older and some current dictionaries but is far from prevalent in American speech today. In fact, the Oxford Dictionary of Pronunciation (2003) says the short i is British and -tee- is American. The variant with a long i in the second syllable (like tie) appears in dictionaries but is an overpronunciation. (“Don’t bother with long i” in anti-, the orthoepist Alfred H. Holt advised in his 1937 guide You Don’t Say. “Just rhyme anti- with panty.”) Also avoid pronouncing the antepenultimate syllable -bi- like be; say it like by. — The Orthoepist

    December 1, 2010

  • Compare pronunciation of the second syllable here with that in antigen.

    December 1, 2010