In Jainism, the term "parva" can refer to a "cycle" or "epoch" in the context of time measurement. Specifically, in Jain cosmology, the unit "pūrvāṅga" or "pūrva" is used to denote extremely large periods of time, but "parva" is not typically used as a standard unit of years in Jain time calculations.

However, if you are asking about the divisions of time in Jain cosmology, here is a brief outline:

• The Jain time cycle (Kālacakra) is divided into two halves: Utsarpiṇī (ascending) and Avasarpiṇī (descending), each consisting of six eras (ārās).
• The smallest standard time units used in Jain cosmology are samaya, avalikā, muhūrta, prahara, and day.
• Larger divisions include years, pūrva, and sagara.
• "Pūrva" is a vast measure of time, much larger than a year.

If you are referring to a festival (parva) such as Paryushana Parva or Diwali Parva, these are not measured in years but are annual events.

If you meant a different context for "parva," please clarify, as Jain scriptures do not define "parva" as a specific number of years. Let me know if you have a more specific reference or context in mind.