Nikini poya is the full moon day in the lunar month of Nikini (in August). Nikini commemorates three months after the passing away of The Buddha. It also marks the conducting of the first Dhamma Sangayana (council or convocation) when 500 monks met at the Sattapanni cave in Rajagahanuwara on a Nikini Full Moon Poya day in order to settle the Buddhist canon.

There are twelve or thirteen poya days per year. Their names correspond to the Buddhist lunar months of the same name. They are VesākPosonEsalaNikiniBinaraVapIllUnduvapDuruthuNavamMedin and Bak.

If a month has two full moon days, the name of the second one is preceded by Adhi (meaning extra in Sinhala) as in Adhi Nikini poya, etc.

Origin:

Pali, Sanskrit, Sinhalese