ˈæftɚ ðˈæt, sˌʌm ˈɔːθɚz ɪnðə jˌuːˌɛsˌɛsˈɑːɹ jˈuːzd ðə wˈɜːd "kˈæɾɐkˌoʊm" tə dˈɛzɪɡnˌeɪt ᵻklˌiːzɪˈæstɪkəl ˌɑːpəzˈɪʃən tə ðə mˈɑːskoʊ pˈeɪtɹɪˌɑːɹkeɪt, wˌaɪl ˈʌðɚz jˈuːzd ɪɾ æz ɐ tˈɛknɪkəl tˈɜːm æz ɐ sˈɪnənˌɪm fɚðɪ ˈɛpɪθɪt "ɪlˈiːɡəl" fɹʌmðə pˈɔɪnt ʌv vjˈuː ʌv sˈoʊviət lˌɛdʒɪslˈeɪʃən.
After that, some authors in the USSR used the word "catacomb" to designate ecclesiastical opposition to the Moscow Patriarchate, while others used it as a technical term as a synonym for the epithet "illegal" from the point of view of Soviet legislation.