Dear list member! The etymology of "tretA" is "tri", but what is the etymology of the numeral "tri"? Probably, the tibetan tranlators find the answer in Yaska's Nirukta (3.10): "eka itA saMkhyA, dvau drutatarA saMkhyA, trayas tIrNatamA saMkhyA....etc." Yours S.Tawaststjerna