CCCP is (or was) the Russian initials for what we call the Union of Soviet Socialist Republics. However, you should realise that in the Russian alphabet (aka the Cyrillic alphabet) C is equivalent to our S, and P to our R. In approximately, phonetic English spelling the words for which CCCP stands are "Souyz (C) Sovetskih (C) Socialistitcheskih (C) Respublik (P).