An enumerated power is

The Constitution creates a Federal Government of enumerated powers." For the first time in sixty years the Court found that in creating a federal statute, Congress had exceeded the power granted to it by the Commerce Clause.

The powers of the federal government that are specifically described in the Constitution are sometimes called 'delegated' or 'expressed powers,' but most often they are known as 'enumerated powers,' and they describe how a central government with three distinct branches can operate effectively.