inhibitor

noun

in·​hib·​i·​tor in-ˈhi-bə-tər 

: 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

All patients were treated with immune checkpoint inhibitors, a type of immunotherapy drugs that help the immune system recognize and attack tumor cells more effectively. —Melissa Rudy, FOXNews.com, 23 Oct. 2025

BioAge is likely to see upside from its novel obesity treatment, BGE-102, a highly potent small-molecule NLRP3 inhibitor, according to Citi. —Liz Napolitano, CNBC, 22 Oct. 2025

For hormone-receptor–positive cancers—the most common type in midlife women—CDK inhibitors like palbociclib, ribociclib and abemaciclib have been game-changing. —Lauryn Higgins, Flow Space, 21 Oct. 2025

Tyramine can suddenly raise blood pressure when combined with monoamine oxidase inhibitors (MAOIs), a type of antidepressant. —Merve Ceylan, Health, 20 Oct. 2025

Word History

First Known Use

circa 1611, in the meaning defined above

Phrases Containing inhibitor

• ACE inhibitor
• protease inhibitor
• proton pump inhibitor
• selective serotonin reuptake inhibitor

Rhymes for inhibitor

• exhibitor

Medical Definition

inhibitor

noun

in·​hib·​i·​tor in-ˈhib-ət-ər 

: 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