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Catalyst

KAT-uh-list /ˈkætəlɪst/

nounC1GRESAT

FormalScientific

A substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.

Catalysts are crucial in industrial processes and biological systems (where they are called enzymes) because they allow reactions to occur faster or at lower temperatures.

The story behind the word. The word 'catalyst' comes from the Greek word 'katalysis,' meaning 'dissolution' or 'unloosing.' This term was introduced into chemistry in 1836 by Jöns Jacob Berzelius, who observed that certain substances could 'unloose' or facilitate reactions without themselves being permanently altered. The idea is that the catalyst helps 'break apart' the old bonds to form new ones more easily.

Word relationships

Accelerator: Emphasizes the speed-increasing aspect, but 'catalyst' implies remaining unchanged.
Stimulant: Something that causes activity or development, but not necessarily in a chemical reaction context or without being consumed.

Inhibitor: A substance that slows down or prevents a chemical reaction.

Word family

catalyze (verb): To cause or accelerate a reaction as a catalyst.
catalytic (adjective): Relating to or involving catalysis.
catalysis (noun): The acceleration of a chemical reaction by a catalyst.

Collocations

chemical catalyst
biological catalyst
positive catalyst
catalyst for change

Idioms & expressions

a catalyst for change

Example sentences

"The enzyme acts as a catalyst, speeding up the digestion of food in the stomach without being consumed in the process." Enzymes are biological catalysts.
"Her passionate speech proved to be the catalyst for widespread social reform, inspiring many to take action." A catalyst for change.

Memory hook

Think of a 'catalyst' as something that 'cuts through' the difficulty of a reaction, making it faster without getting cut itself. Cuts through

When not to use

Do not use 'catalyst' to describe something that merely initiates a process without accelerating it or remaining unchanged itself.

Fun facts

Catalysts are essential for many industrial processes, including the production of plastics, fuels, and fertilizers.
The catalytic converter in cars uses catalysts to convert harmful pollutants into less toxic substances.