From Wikipedia, the free encyclopedia.
1) With a lower case C catholic means universal. It is in this sense that the word is used in general but also by some Protestant churches.
2) With both C's capitalised, Catholic Church refers to (and is the official name of) the Catholic Church.
4) Without the capital C on church, Catholic church refers to any of a number of other churches which have split from the Catholic Church, but they do not consider themselves Protestant. These include the Ancient Catholic Church, Old Catholic Church, Liberal Catholic Church the Chinese Patriotic Catholic Association, and some elements of Anglicanism ("High Church Anglicans" or "Anglo-Catholics").
See also Catholicism.