Step 1: Purana Definition.
Puranas are ancient Hindu texts detailing mythology, cosmology, genealogies, and cultural traditions.
The classical definition of a Purana encompasses five characteristics, termed Panchalakshana: creation (sarga), recreation (pratisarga), genealogies (vamsha), reigns of Manus (manvantara), and dynastic histories (vamshanucharita).
Step 2: Identification in Vishnupurana.
The Vishnupurana explicitly defines a Purana by elaborating on these characteristics.
Step 3: Exclusion of Other Puranas.
- Brahmapurana: Contains creation narratives but lacks a formal Purana definition.
- Skandapurana: Focuses on pilgrimages and local traditions, not on defining Purana.
- Markandeyapurana: Notable for its Devi Mahatmya, not for defining Purana.
Step 4: Conclusion.
Therefore, the Vishnupurana is the Purana that provides the definition of a Purana.