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 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 In February 2018, Bristol Myers agreed to pay $1.85 billion, with a combination of cash and Nektar share purchases, to develop bempeg with Bristol’s checkpoint inhibitor Opdivo. Joseph Walker, WSJ, 11 May 2022 Alternatively, your doctor may recommend a topical calcineurin inhibitor like tacrolimus or pimecrolimus as an alternative or in addition to steroids. Stephanie Watson, SELF, 8 Apr. 2022 Quinapril is an angiotensin-converting enzyme (ACE) inhibitor that prevents blood vessels from narrowing, while hydrochlorothiazide is a diuretic, which causes a person to urinate more and flushes out sodium in the body. Sophie Mellor, Fortune, 23 Mar. 2022 As a cholinesterase inhibitor, donepezil works by inhibiting cholinesterase, an enzyme that breaks down acetylcholine, aiming to preserve the patient's level of this neurotransmitter. Mariana Lenharo,, 13 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

24 Jun 2022

Cite this Entry

“Inhibitor.” Dictionary, Merriam-Webster, Accessed 28 Jun. 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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