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

By that time, she had been given a dose of an immune checkpoint inhibitor, an immunotherapy drug designed to make her immune cells more effective in fighting cancer. —Caleb Hellerman, CNN Money, 20 Apr. 2026

Those are often sprayed with a sprout inhibitor that will also keep them from growing. —Karen Brewer Grossman, Southern Living, 20 Apr. 2026

Beyond Revolution Medicines, dozens of other companies are also testing promising KRAS inhibitors in the clinic. —Angus Chen, STAT, 19 Apr. 2026

Icoytde belongs to the same class of drugs as Tremfya and rival shots like AbbVie's Skyrizi, known as IL-23 inhibitors. —Kevin Stankiewicz, CNBC, 14 Apr. 2026

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