Ruthu

Ritu (ऋतु) defines "season" in different ancient Indian calendars used in countries of Pakistan, India, Bangladesh, Nepal and Sri Lanka, and there are six ritus (also transliterated rutu) or seasons. The word is derived from the Vedic Sanskrit word Ṛtú, a fixed or appointed time, especially the proper time for sacrifice (yajna) or ritual in Vedic religion; this in turn comes from the word Ṛta (ऋत), as used in Vedic Sanskrit literally means the "order or course of things". This word is used in nearly all Indian languages.

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