Extraordinary minister of Holy Communion

"An extraordinary minister of Holy Communion in the Catholic Church is, under the Code of Canon Law, "an acolyte, or another of Christ's faithful deputed", in certain circumstances, to distribute Holy Communion. The term "extraordinary" distinguishes such a person from the ordinary (normal, regular) minister of Holy Communion, namely a bishop, priest or deacon"

"Function

The extraordinary minister's function is to distribute Holy Communion, either within Mass or by taking it to a sick person, when an ordained minister (bishop, priest or deacon) is absent or impeded.
In order to avoid confusion about this function, an extraordinary minister of Holy Communion is not to be called a "special minister of Holy Communion", nor an "extraordinary Minister of the Eucharist", nor a "special minister of the Eucharist".

Ten years before publication of the present Code of Canon Law, some of these expressions were used in the instruction of the Sacred Congregation of the Sacraments Immensae caritatis of 29 January 1973. They are now reprobated.
The only minister of the Eucharist is the priest"

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More info....
 Extraordinary Ministers of Holy Communion at Mass
Questions About Eucharistic Ministers