when did the term catholic first used?

Answer 1

Catholic with a capitol "C" refers to the Catholic Church
catholic with a small "c" means universal.

Answer 2

It goes back to the early days of the Christian church. The term is from the Greek word Katolikos meaning universal. It really had nothing to do with the way it is now used to describe a particular branch of the church ie: Catholic.

Answer 3

The Church has referred to itself as the “Catholic Church” at least since 107 C.E. (about 10 years after the last book of the New Testament was written), when the Greek term "Katholikos" (meaning universal) appears in the Letter of St. Ignatius of Antioch to the Smyrnaeans:

"Wherever the bishop appear, there let the multitude be; even as wherever Christ Jesus is, there is the Catholic Church."

http://www.earlychristianwritings.com/text/ignatius-smyrnaeans-hoole.html

We do not know how long they had been using the term "Catholic" before it was included in this letter.

All of this was long before the Council of Nicea and the Nicene Creed from 325 C.E. which states, "We believe in one, holy, catholic, and apostolic Church."

http://www.newadvent.org/cathen/07644a.htm

With love in Christ.