catalyst What is the Definition of catalyst?Noun:(chemistry)something that causes an important event to happen Other meanings of catalyst (synonyms, cognates). ENRU catalyst катализатор Frequently viewed: fast meaningmyself meaningpresent definitionwarm in a sentenceblind in a sentencerecently meaningdouble definitiondefinition of keyteam in a sentencehot meaningsucceed definitioncoffee meaning A B C D E F G H I J K L M N O P Q R S T U V W X Y Z