in·​hib·​i·​tor | \ in-ˈhi-bə-tər How to pronounce inhibitor (audio) \

Definition of inhibitor

: one that inhibits: such as
a : an agent that slows or interferes with a chemical action
b : a substance that reduces or suppresses the activity of another substance (such as an enzyme)

Examples of inhibitor in a Sentence

Recent Examples on the Web Recently, Vertex announced that VX-548, a Nav1.8 inhibitor, had outperformed a placebo in phase 2 trials for acute pain after two types of surgery. Margaret Osborne, Smithsonian Magazine, 30 June 2022 Wood says drugs like the Nav1.8 inhibitor from the pharmaceutical company Vertex, which is administered in pill form, have shown strong pain relieving effects in humans. Margaret Osborne, Smithsonian Magazine, 30 June 2022 Mirati’s drug, a KRAS inhibitor, was studied in 19 patients with the condition, and 32% of them responded positively to the drug. Aayushi Pratap, Forbes, 10 June 2022 In 2014, Amgen sued its partners Sanofi and Regeneron over alleged patent infringement on its PCSK9 inhibitor, Repatha, successfully scuttling the drug’s launch in the U.S. market. Megan Molteni, STAT, 4 Apr. 2022 Consistently, in structural biology analyses, the different substitutions reduced the number of interactions between the inhibitor and the enzyme. William A. Haseltine, Forbes, 9 June 2022 But Diaz had been looking for a way to test moving Keytruda or a drug like it, known as a checkpoint inhibitor, in patients whose cancer had not spread. Matthew Herper, STAT, 8 June 2022 The researchers believed that dostarlimab, a checkpoint inhibitor that exposes cancer cells to allow the immune system to fight them, would work well in the patients. Julie Mazziotta,, 6 June 2022 The lack of guardrails is the principal inhibitor to a well-functioning ESG investment ecosystem. R. Mukund, Forbes, 25 Apr. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'inhibitor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of inhibitor

circa 1611, in the meaning defined above

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Time Traveler for inhibitor

Time Traveler

The first known use of inhibitor was circa 1611

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Dictionary Entries Near inhibitor



in high dudgeon

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Last Updated

30 Jul 2022

Cite this Entry

“Inhibitor.” Dictionary, Merriam-Webster, Accessed 11 Aug. 2022.

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More Definitions for inhibitor


in·​hib·​i·​tor | \ in-ˈhib-ət-ər How to pronounce inhibitor (audio) \

Medical Definition of inhibitor

: one that inhibits: as
a : an agent that slows or interferes with a chemical reaction
b : a substance that reduces the activity of another substance (as an enzyme)
c : a gene that checks the normal effect of another nonallelic gene when both are present


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