Any of several Protestant groups strongly influenced by Calvinism .
They are often called by national names (Swiss Reformed, Dutch Reformed, etc.). The name was originally used by all the Protestant churches that arose out of the 16th-century Reformation but was later confined to the Calvinistic churches of continental Europe, most of which use a Presbyterian form of church government. The Calvinistic churches of the British Isles became known as Presbyterian churches (see Presbyterianism ).