Both churches have always identified themselves as "Catholic", or universal in the Greek language (katholikos). Orthodox Churches still use the creed in every

Both churches have always identified themselves as "Catholic", or universal in the Greek language (katholikos). Orthodox Churches still use the creed in every service, where they say "We believe in one holy catholic and apostolic church". Also, it's not like the Roman Catholics claim to be heterodox or something, they also claim that their faith is "orthodox".