catalyst

A person or thing that helps an important change begin or happen faster.

• The protest became a catalyst for change.
• Her arrival acted as a catalyst for reform.
• Could this discovery be a catalyst for further research?

How to use it: catalyst for something (The crisis was a catalyst for reform.)

Similar words: spark, stimulus

Common phrases: catalyst for change, act as catalyst, catalyst for something

A substance that makes a chemical change happen faster without being used up.

• The reaction needs a catalyst.
• Platinum acts as a catalyst in this process.
• Scientists tested several catalysts to speed up the reaction.

Common phrases: chemical catalyst, use a catalyst, catalyst in something

A device in a vehicle that makes harmful exhaust gases less harmful.

• The mechanic replaced the catalyst.
• A damaged catalyst can increase exhaust pollution.
• This car needs a new catalyst to pass inspection.

Similar words: catalytic converter

Common phrases: exhaust catalyst, replace a catalyst, damaged catalyst