In Jain Dharma, “Pakkhi” (also written Pakshi / Pakshik) usually means:

Fortnightly (every 15 days) religious observance.

Most commonly it is used in two ways:

1. Pakkhi Pratikraman

- A special Pratikraman done once every fortnight (on the 14th tithi – Chaturdashi – of each lunar paksh). - It is a longer, more detailed repentance and reflection compared to daily Pratikraman.

1. Pakkhi Upvas / Niyam

- A regular vow to do special sādhanā every fortnight, e.g.: - Upvas (full fast) - Ekasanu / Ayambil - Extra Pratikraman or Paushadh on that day.

So, in Jain usage, “Pakkhi” means a fixed, repeated practice done every paksh (fortnight), especially Pratikraman or Upvas.

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