Which term describes a substance that speeds up a chemical reaction without being consumed in the process?

A catalyst is a substance that accelerates a chemical reaction without undergoing any permanent chemical change itself. This means that after the reaction occurs, the catalyst can be reused to facilitate additional reactions. Catalysts work by lowering the activation energy needed for a reaction to occur, allowing it to proceed more quickly and efficiently.

While enzymes are indeed a specific type of catalyst that are biological in nature, the broader term that encompasses both biological and chemical catalysts is "catalyst." Reagents are substances that are consumed or transformed during a chemical reaction, while activators may refer to molecules that increase the activity of enzymes or other biological processes but do not broadly define the role of substances that speed up reactions without being consumed. Thus, the most accurate term for a substance that speeds up a chemical reaction without being used up is indeed a catalyst.