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

The latest example involved a group of drugs called BACE inhibitors, meant to block an enzyme key to the formation of amyloid plaques. Damian Garde, STAT, "Biogen reports positive results with Alzheimer’s drug, reviving hopes for once-failed treatment," 5 July 2018 UC Davis oncologist David Gandara reported a retrospective analysis of seven different trials of the checkpoint inhibitor Tecentriq in lung and bladder cancer, melanoma, and other tumors. Ken Garber, Science | AAAS, "Mutation-counting blood test could predict if cutting-edge immunotherapies can beat a cancer," 27 June 2018 The inhibitor is administered to patients through an infusion. Cindy Goodman, miamiherald, "Immunotherapy is giving some cancer patients a new life when they had all but given up," 25 May 2018 When the inhibitor was present, the RNA had no effect on the animals it was injected into. John Timmer, Ars Technica, "Researchers claim to have transferred a memory between two sea slugs," 16 May 2018 A year ago, the future of IDO inhibitors looked bright. Ken Garber, Science | AAAS, "A promising new cancer drug has hit a major setback, raising questions about whether the field is moving too fast," 9 May 2018 All three are in a class called neuraminidase inhibitors. NBC News, "New, fast-acting flu drug gets priority FDA review," 26 June 2018 The drug was nivolumab, or Opdivo, which belongs to a class called checkpoint inhibitors. Denise Grady, New York Times, "A Promising Cancer Treatment Made Patients Worse, Not Better," 5 June 2018 Helping Cancer Drugs Hit Their Molecular Mark The SKI scientists demonstrated the effectiveness of their nanoparticles using drugs called MEK inhibitors. Matthew Tontonoz, Scientific American, "Up Close and Personal," 15 May 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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8 Sep 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

Comments on inhibitor

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the setting in which something occurs

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