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

Ajax’s lead asset is an investigational, once daily, oral Type II JAK2 inhibitor that’s being studied in a Phase 1 trial in patients with the rare blood cancer myelofibrosis who previously were treated with a Type 1 JAK2 inhibitor. —Jeff Marks, CNBC, 27 Apr. 2026

The pharmaceutical industry has become extraordinarily good at creating these inhibitors, each designed to shut down a particular pathway. —IEEE Spectrum, 27 Apr. 2026

The promise of a better pan-RAS inhibitor Erasca has been described as the poor man’s Revolution Medicines. —Adam Feuerstein, STAT, 23 Apr. 2026

Enzyme Inhibitor Peptides Enzyme inhibitor peptides help to prevent the breakdown of collagen, preserving the skin’s structure and slowing visible signs of aging. —Brianna Peters, Vogue, 22 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