inhibitor

American  

[in-hib-i-ter] / ɪnˈhɪb ɪ tər /

Or inhibiter

noun

1. a person or thing that inhibits.

2. Chemistry. a substance that decreases the rate of or stops completely a chemical reaction.

3. any impurity in a mineral that prevents luminescence.

4. Rocketry. an inert antioxidant used with solid propellants to inhibit burning on certain surfaces.

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inhibitor British  

/ ɪnˈhɪbɪtə /

noun

1. Also called: inhibiter.  a person or thing that inhibits

2. Also called: anticatalyst.  a substance that retards or stops a chemical reaction Compare catalyst

3. biochem

   1. a substance that inhibits the action of an enzyme

   2. a substance that inhibits a metabolic or physiological process

      a plant growth inhibitor

4. any impurity in a solid that prevents luminescence

5. an inert substance added to some rocket fuels to inhibit ignition on certain surfaces

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Etymology

Origin of inhibitor

First recorded in 1865–70; inhibit + -or ²

Explanation

An inhibitor is a substance or material that slows down or halts some activity. This word is popular in the chemistry lab, but you might also hear it at a garage. For example, a corrosion inhibitor helps slow down rust. When you feel inhibited, you feel self-conscious and less likely to do things. In chemistry, an inhibitor has the effect of squelching something, shutting it down, or slowing it. For example, in a car engine, antifreeze is an inhibitor — it prevents or slows the formation of ice. Different substances are inhibitors for different reactions and activities. Think of an inhibitor as chemistry's way of saying "Slow down!" or "Stop!"

Example Sentences

See Examples For:

inhibitor

In addition to acting as an ACC inhibitor, it activates PPARα and PPARδ, cellular receptors that switch on genes involved in taking up fat and burning it for energy.

From Science Daily ● Aug. 23, 2026

Steve Chalke, founder of Oasis Academy, which runs more than 50 schools across England, says the heatwaves were a "real inhibitor" to teaching.

From BBC ● Aug. 22, 2026

So does the glowing inhibitor on his spine, which seems to ask if we’re too quick to prescribe medication for our problems.

From Los Angeles Times ● Jul. 30, 2026

Sino Biopharmaceutical said subsidiary Chia Tai Tianqing Pharmaceutical granted AstraZeneca exclusive rights to develop, manufacture and commercialize its new PDE3/4 inhibitor, TQC3721, outside China.

From The Wall Street Journal ● Jul. 8, 2026

The difference between an antienzyme, which protects material which would otherwise be subject to the attack of an enzyme, and an inhibitor, which renders the enzyme itself inactive, is apparent.

From The Chemistry of Plant Life by Roscoe Wilfred Thatcher

Related Words

• avoidance