in·​hib·​i·​tor | \in-ˈhi-bə-tər \

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

Next, the effectiveness of the enzyme inhibitor needs to be tested against the entire virus, not just the enzyme. Bradley J. Fikes,, "UCSD discovery points way to possible universal flu drug," 20 Mar. 2018 Last year, Javid Moslehi, director of cardio-oncology at the Vanderbilt University Department of Medicine, reported on two patients who developed myocarditis after being treated with a combination of two checkpoint inhibitors and quickly died. Laurie Mcginley, Washington Post, "New cancer treatments have perplexing side effects," 6 Mar. 2018 And then, in the late 1980s there’s the arrival of serotonin reuptake inhibitors, known as SSRIs, and their promise to be different from the antidepressants of the past. Maggie Jones, New York Times, "A Reckoning With an Imperfect Science in ‘Blue Dreams’," 3 Apr. 2018 The checkpoint inhibitors allow powerful immune cells to recognize and hone in on cancer cells and co-opt killer cells to destroy them. Alice Park, Time, "There's More Good News About Immune Therapies for Cancer," 12 July 2018 These treatments include the checkpoint inhibitors Keytruda and Opdivo, CAR-T drugs such as Yescarta and Kymriah, and neo-antigen vaccines. Casey Ross, STAT, "A new cancer care dilemma: Patients want immunotherapy even when evidence is lacking," 4 June 2018 But niacin, a B vitamin, has many side effects, and PCSK9 inhibitors, which are not approved for lp(a) lowering, are not usually covered by insurance for that purpose and can cost as much as $14,000 a year. Anahad O’connor, New York Times, "A Heart Risk Factor Even Doctors Know Little About," 9 Jan. 2018 Tamiflu and a few other flu drugs are neuraminidase inhibitors. Beth Mole, Ars Technica, "This novel, one-and-done flu drug could be available soon in the US," 27 June 2018 According to the World Anti-Doping Agency, letrozole is an aromatase inhibitor that can act as a hormonal and metabolic stimulant by increasing testosterone concentration. Bianca Britton, CNN, "Tennis player Sara Errani 'disgusted' by doping ban increase," 12 June 2018

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.

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First Known Use of inhibitor

circa 1611, in the meaning defined above

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Last Updated

3 Nov 2018

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The first known use of inhibitor was circa 1611

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in·​hib·​i·​tor | \in-ˈhib-ət-ər \

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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More from Merriam-Webster on inhibitor

Nglish: Translation of inhibitor for Spanish Speakers

Britannica English: Translation of inhibitor for Arabic Speakers Encyclopedia article about inhibitor

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playful or foolish behavior

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