Definitions for "Presbyterianism"
That form of church government which invests presbyters with all spiritual power, and admits no prelates over them; also, the faith and polity of the Presbyterian churches, taken collectively.
the doctrines and practices of the Presbyterian Church: based in Calvinism
the form of church government in which Elders and Ministers govern through 'courts' (as opposed to government involving Bishops - 'episcopacy')