Dear সুজাতা ঘোষ,
Check the above if you can see your name in Bengali script (If the writing is distorted, and you are on a recent windows machine, go an enable Thai-like complex text support in international preference; on a mac see
http://tanmoy.tripod.com/mac.html).
And, one irrelevant point out of the way: I am তন্ময় ভট্টাচার্য্য, but this site truncates the last name in the author's field.
Okay, I have never heard AYan (আয়ন) in Ayan vAYu (আয়ন বায়ু ). If you can refer me to some literature or some dictionary (I checked Haricharan Bandyopadhyay's Bangiya shabdakosh, for example), that will help.
The meaning of AYan, as far as I know, is two fold: one means arrival, but Agaman (আগমন) is more common word for that. The other one, which is what I think relevant for us means `related to solistice'. Fundamentally, this is the same word: the solistice is obviously defined in terms of the motion of the sun. The most common usage in Bengali (technically of the noun ayan (অয়ন) from which the adjective Ayan (আয়ন) is derived) is in the words uttarAYaNa (উত্তরায়ণ) and dakSiNAyana (দক্ষিণায়ন) referring to the (northern hemisphere) summer and winter motions of the sun. The alteration of retroflex N (ণ) versus the dental n (ন) at the end is merely a phonological grammatical phenomenon.
But why would it be a name: probably because it sounds good to modern Bengali ear (because of similar sound patterns in other names). But, it does have rich connotations to a slightly older generation. Apart from possible astrological significance which I cannot immediately recall, even I would subconsciously associate the word primarily with the constancy of division of the year into summer and winter, the unending cycle that governs the seasons. Secondarily, I would associate it with cyclical transitions that are essentially life giving. And finally, may be, with being the northernmost or southernmost point in the motion of the sun: Jun 21/22 and December 21/22 today, shifting earlier by about a day every 72 years.
I hope this post was useful. If you find anything about the AYan vAYu reference, please post it here, or communicate directly at my email address, as you choose.
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