The article is devoted to an understudied topic — the grammatical features of religious vocabulary referring to various confessions and their adequate refl ection in general explanatory dictionaries. The study uses materials from the new “Academic Explanatory Dictionary of the Russian Language”, which is being developed at the Vinogradov Russian Language Institute of the Russian Academy of Sciences. Grammatical information in the explanatory dictionary is located in two zones of the dictionary entry — in the zone of grammatical forms and in the zone of grammatical (morphological or syntactic) characteristics. Dictionary illustrations also play an important role in demonstrating the grammatical properties of religious vocabulary. The article deals with examples of inaccurate, incomplete lexicographic representation of both grammatical forms and grammatical characteristics of words with religious meaning. The paper shows that the grammatical description of confessional vocabulary cannot be properly implemented without a careful study of living speech usage and revision of some traditional lexicographic solutions. The examples given reveal the connection between grammar and accentology (see the accent scheme of prosphorá ‘the communion bread’ / prosvirá variants below), spelling (the fl uctuations in the spelling of the dative and prepositional cases of the lexeme utrenya ‘the matins’), lexical semantics (the homonym passiya² ‘the service of Great Lent’, characterized as “inanimate”). It is noted that special attention should be paid to words that have come into active use in recent decades (see, for example, different grammatical status of halal’ ‘permitted food in Islam’ — as a lexeme, belonging to different parts of speech, or as a morpheme).