Nope. Orthodox Catholic is interchangeable with Orthodox Christian. This is an OCA church for example: 
Discussion
Confusing! What is the purpose of adding “Catholic” when the Orthodox and Catholic schism exists?
It literally wasn’t added after the schism. Catholic means universal. That’s why Romans, Orthodox, and most Protestants all say “I believe in one holy catholic apostolic church” in the creed. Anglo-Catholics and old Catholics and orthodox Catholics are all *not* in communion with Roman Catholics. Romans have never owned the word Catholic they’re just the largest group.
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It's like how people from the USA are called "Americans", but Canadians and etc. are also Americans.
I try to clarify with capitalization. I'm an "orthodox Catholic", but not an "Orthodox Catholic".
That confuses people, too, as I'm using "orthodox" to clarify that I'm neither trad, nor liberal.