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 Some also had methicillin-resistant Staphylococcus aureus (MRSA). Allison Parshall, Scientific American, 16 May 2022 One, for example, proved to be extremely effective against both anthrax (Bacillus anthracis) and MRSA (methicillin-resistant Staphylococcus aureus), a notorious superbug that has become resistant to many common antibiotics. Stephanie Stone, Smithsonian Magazine, 2 Sep. 2021 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,, 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, 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, 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, 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, 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, 12 June 2019 See More

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.

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

Time Traveler

The first known use of methicillin was in 1961

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Statistics for methicillin

Last Updated

20 May 2022

Cite this Entry

“Methicillin.” Dictionary, Merriam-Webster, Accessed 26 May. 2022.

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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


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