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

Serotonin-norepinephrine reuptake inhibitors or SNRIs such as Cymbalta, Fetzima and Effexor XR prevent the reabsorption of serotonin and norepinephrine, which help shape the body’s fight-or-flight response. — Jen Christensen, CNN Money, 29 Aug. 2026

The tablet combines bictegravir, the backbone of Gilead’s blockbuster HIV pill Biktarvy, with lenacapavir, a first-in-class capsid inhibitor that has become a centerpiece of the company’s long-term strategy for HIV treatment and prevention. — Justina Lee, CNBC, 28 Aug. 2026

The study, published in the British Journal of Ophthalmology, compared about 37,000 men prescribed tadalafil with a similar group who did not use phosphodiesterase type 5 inhibitors, the drug class that includes Cialis. — Kelly McGreal, FOXNews.com, 23 Aug. 2026

How to fade the spots The most effective ingredients for fading these marks are tyrosinase inhibitors, which work by blocking the enzyme your skin uses to produce melanin. — Leslie Baumann, Miami Herald, 20 Aug. 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