meth·​i·​cil·​lin | \ ˌme-thə-ˈsi-lən How to pronounce methicillin (audio) \

Definition of methicillin

: a semisynthetic penicillin C17H19N2O6NaS used especially in the form of its sodium salt against beta-lactamase-producing staphylococci

Examples of methicillin in a Sentence

Recent Examples on the Web Montoya was stable and improving slightly, but after a week on the ventilator, doctors found MRSA, methicillin-resistant Staphylococcus aureus, in her lungs. Julie Mazziotta,, "Texas Mom Begs People to ‘Put Your Masks On’ in Tearful Video Days Before Dying from Coronavirus," 19 Aug. 2020 The superbug is resistant to beta-lactam antibiotics, a broad-spectrum group which includes methicillin as well as oxacillin and the cephalosporins. Ranjit Devraj, Quartz India, "Superbugs have returned to haunt India’s hospitals," 23 July 2019 The circuit switched off in response to the detection of genetic material from pathogens including the Ebola virus and methicillin-resistant Staphylococcus aureus (MRSA). Ewen Callaway, Scientific American, "Gene Editing Transforms Gel into Shape-Shifting Smart Material," 23 Aug. 2019 Superbug surveillance Chief among the microbes under surveillance is methicillin-resistant Staphylococcus aureus (MRSA), which is commonly found in hospitals and in patients who have undergone procedures involving invasive devices such as catheters. Ranjit Devraj, Quartz India, "Superbugs have returned to haunt India’s hospitals," 23 July 2019 The peril of overusing antibiotics became apparent in the 1990s when MRSA (short for methicillin-resistant Staphylococcus aureus), a deadly superbug, began terrorising hospitals in Europe and America. The Economist, "Attack of the superbugs: July 2041," 5 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 Methicillin-resistant Staphylococcus aureus, or MRSA, is one well-known example: Resistant strains appeared soon after the antibiotic methicillin was introduced in the 1950s, and now MRSA is a scourge in hospitals worldwide. Quanta Magazine, "‘Broadband’ Networks of Viruses May Help Bacteria Evolve Faster," 16 Oct. 2018 A month later, her father contracted methicillin-resistant Staphylococcus aureus. Rachel Leingang, azcentral, "Former employee sues ASU, claiming violation of federal medical leave law," 19 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'methicillin.' 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 methicillin

1961, in the meaning defined above

History and Etymology for methicillin

meth- + penicillin

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Time Traveler for methicillin

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The first known use of methicillin was in 1961

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Cite this Entry

“Methicillin.” Dictionary, Merriam-Webster, Accessed 11 May. 2021.

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More Definitions for methicillin


meth·​i·​cil·​lin | \ ˌmeth-ə-ˈsil-ən How to pronounce methicillin (audio) \

Medical Definition of methicillin

: a semisynthetic penicillin C17H19N2O6NaS that is especially effective against beta-lactamase producing staphylococci

Comments on methicillin

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