The Arabic vocative presents a problem of grammatical description because its syntactic position does not always correspond to an overt accusative ending. This article examines how Ziyāʾ al-Dīn al-Makkī al-Khwārazmī explains that relationship in Kifāyat al-naḥw fī ʿilm al-iʿrāb. A qualitative philological analysis is applied to the vocative passages transcribed in the study materials from manuscript no. 10518, held at the Abu Rayhan Beruni Institute of Oriental Studies, Academy of Sciences of Uzbekistan. Selected comparisons with al-Zamakhsharī’s Al-Mufaṣṣal and al-Sakkākī’s Miftāḥ al-ʿulūm contextualize the treatment within classical Arabic grammar. The analysis identifies four connected expository principles: locating the vocative within accusative government; conditioning overt case marking on nominal structure and referential specificity; distinguishing surface form from syntactic position in dependent expressions; and extending the basic account to constructions of mediation, possession, and expressive address. The findings support an interpretation of the discussion as a coherent account of grammatical government rather than a list of vocative forms. Its distinctive value lies in the organization and integration of established grammatical explanations. The study does not claim the invention of these rules or establish direct influence on later grammarians. Its conclusions remain limited to the transmitted excerpts and bibliographic evidence available for analysis.