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

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 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 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 Increasingly, doctors need to administer intravenous antibiotics—as in Osbourne's case—to treat serious staph infections as more strains, like MRSA (methicillin-resistant Staphylococcus aureus), develop resistance to the usual treatment. Carolyn L. Todd, SELF, "Ozzy Osbourne Underwent Hand Surgery to Treat Multiple Staph Infections: ‘It Was Agony’," 23 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 The bacteria involved are resistant to not only methicillin but also amoxicillin, penicillin and oxycillin. Cathie Anderson, sacbee, "Influenza B surging as overall flu cases fall — and it's deadlier in kids, experts say | The Sacramento Bee," 19 Mar. 2018 Medicare also examines rates of methicillin-resistant Staphylococcus aureus, or MRSA, and Clostridium difficile, known as C-diff. Jordan Rau, Washington Post, "Half Of Hospitals In Conn., Del. Hit By Medicare’s Safety Penalties," 5 Jan. 2018 In early tests in rats infected with methicillin-resistant Staphylococcus aureus (MRSA), the researchers found that the molecules were able to sterilize the infection area. Alexandra Sifferlin, Time, "A Potentially Powerful New Antibiotic Is Discovered in Dirt," 14 Feb. 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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Last Updated

13 Jul 2019

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The first known use of methicillin was in 1961

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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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