ChEBI

Originally referring to an endogenous compound that is formed in specialized organ or group of cells and carried to another organ or group of cells, in the same organism, upon which it has a specific regulatory function, the term is now commonly used to include non-endogenous, semi-synthetic and fully synthetic analogues of such compounds.

Any intermediate or product resulting from metabolism. The term 'metabolite' subsumes the classes commonly known as primary and secondary metabolites.