Definition from Wiktionary, the free dictionary
From Sanskrit पुराण (purāṇá, “stories of ancient times told in a new manner”).
Proper noun 
Purana (plural Puranas)
- (Hinduism) Name of an ancient Indian genre (or a group of related genres) of Hindu or Jain literature (as distinct from oral tradition). They are primarily post-Vedic texts containing a narrative of the history of the Universe, from creation to destruction, genealogies of the kings, heroes and demigods, and descriptions of Hindu cosmology, philosophy and geography.