catalyst

catalyseur

Personne ou chose qui favorise le début d’un changement important ou l’accélère.

En anglais simple : 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?

Comment l'utiliser : catalyst for something (The crisis was a catalyst for reform.)

Synonymes : spark, stimulus

Expressions courantes : catalyst for change, act as catalyst, catalyst for something

catalyseur

Substance qui accélère une transformation chimique sans être consommée.

En anglais simple : 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.

Expressions courantes : chemical catalyst, use a catalyst, catalyst in something

pot catalytique

Dispositif d’un véhicule qui rend les gaz d’échappement moins nocifs.

En anglais simple : 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.

Synonymes : catalytic converter

Expressions courantes : exhaust catalyst, replace a catalyst, damaged catalyst