I thought I would make a small contribution to the discussion about Vassuupanaayika. My comments are based on Sri Lankan Practice.
Vassa originally (most probably) meant rain. However, the meaning in religious practice was ' rains retreat',
Upanaayika means for a bhikkhu to begin to observe the rains retreat. Or to commence the vassa observances. A bhikkhu must observe 'Vassa'. It is a disciplinary rule. According to the Sutta it could be early/before or later/after. I have found the dates form a Sinhala book 'Vinaya Kamma Book' by Ven. Rerukaane Chandavimala, generally accepted as an authority in Sri Lanaka, as: July and the other is August (these months are approximate). The actual dates are calculated on the basis of the almanack and the lunar calender.
So as far as the Theravaada tradition is concerned, 'Vassuupanayikaa' refers to the dates on which Vassa commences. .
D. G. D. C. Wijeratna
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