methicillin

noun

meth·​i·​cil·​lin ˌme-thə-ˈsi-lən How to pronounce methicillin (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Roughly 40% of the infections were resistant to treatment with the antibiotic methicillin, the report found. — Fox News, 7 Feb. 2023 Recluse spider lesions can be misdiagnosed due to their similarity to sores from bacteria such as methicillin-resistant Staphylococcus. — Matthew Cordes, The Conversation, 6 Apr. 2026 Young and otherwise healthy people can get a methicillin-resistant Staphylococcus aureus, or MRSA, infection on their skin. — BostonGlobe.com, 14 July 2022 The autopsy showed his condition was the result of methicillin-resistant Staphylococcus aureus pneumonia that, according to the Cleveland Clinic, is a type of MRSA staph infection resistant to antibiotics. — Caleb Lunetta, San Diego Union-Tribune, 15 Aug. 2025 See All Example Sentences for methicillin

Word History

Etymology

meth- + penicillin

First Known Use

1961, in the meaning defined above

Time Traveler
The first known use of methicillin was in 1961

Rhymes for methicillin

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Browse Nearby Words

methexis
methicillin
methicillin-resistant Staphylococcus aureus
See all Nearby Words

Cite this Entry

“Methicillin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/methicillin. Accessed 8 Jul. 2026.

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Kids Definition

methicillin

noun
meth·​i·​cil·​lin ˌmeth-ə-ˈsil-ən How to pronounce methicillin (audio)
: a form of penicillin used especially against certain forms of staphylococcus bacteria

Medical Definition

methicillin

noun
meth·​i·​cil·​lin ˌmeth-ə-ˈsil-ən How to pronounce methicillin (audio)
: a semisynthetic penicillin C17H19N2O6NaS that is especially effective against beta-lactamase producing staphylococci
Last Updated: - Updated example sentences
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