(biology) any agency bringing about activation; a molecule that increases the activity of an enzyme or a protein that increases the production of a gene product in DNA transcription

the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions

a biochemical catalyst such as an enzyme

any of several complex proteins that are produced by cells and act as catalysts in specific biochemical reactions

a fine black powder of platinum; used as a catalyst in chemical reactions

an accelerator that lowers the activation energy of vulcanization reaction.

the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions