There is no doubt that scriptures and treatises in Tibetan translation can be indispensable for tracing and explaining the history of Tibetan language. One important point that we may not always be aware of is that Tibetans themselves might have in course of time forgotten certain aspects of their language. It is thus, for example, not at all easy to reconstruct a meaning of an obscure/obsolete word found in some translated literature for which there is no Sanskrit or other original from which the translation was made. I would like to take the case of ’drob skyong as an example. While the meaning of skyong is not at all a problem, the meaning of ’drob can pose difficulties for individuals like myself.
What does ’drob mean? If we take a look at the brDa dkrol gser gyi me long (s.v. ’drob skyong), we would see that it is explained as drang por skyong ba “to direct/rule/lead justly.” And in the brDa rnying tshig mdzod (s.v. ’drobs) as well as in the Tshig mdzod chen mo (s.v.), ’drobs is explained as drang po “upright, just.” But did ’drob/s once really mean drang po? I doubt. The interpretation of ’drob/s as “upright, just” seems to be influenced by the fact that scholars knew about the occurrence of ’drob only in the context of ’Drob-skyong or ’Drob-skyong-gi-bu, who has been mentioned as a name of a sage (ṛṣi: drang srong). With regard to ’drob skyong, Jäschke, as a well-trained and cautious philologist, provides Schmidt as his source and states “keeper of light,” followed by a question mark. Schmidt must have known the Tibetan translation of Kaśyapa (= Kāśyapa?) in the Mahāvyutpatti (no. 3456) listed there as one of the ṛṣis, as ’Drob-skyong-gi-bu. Kāśyapa is usually translated as ’Od-srung/s, and that must be reason why ’drob can be thought to be equatable with ’od (“light”). But the question still remains if ’drob has been synonymous with ’od. An alternative reading of ’drob in Mahāvyutpatti (no. 3456) is ’dros, which is equally (or even more) obscure to me.
In Old Tibetan Documents Online, ’drob or ’drobs does not occur at all whereas ’dros occurs once. The context and meaning of ’dros here are not clear to me. I have at the moment no satisfactory explanation. Several questions remain open: (a) Is the reading ’drob or ’dros at all correct? Most dictionaries seem to take for granted that the reading ’drob is correct. (b) Could ’drob be synonymous with ’od? (c) Or could ’drob means something completely different? If so, what?
The Tshig mdzod chen po records a word spelt sgrob and it is supposed to mean ’bying nyams dang dregs pa’i rnam ’gyur (“a demeanor/appearance of grandeur and dignity/vanity”). Could it be that sgrob was then spelt ’drob? This would not be implausible particularly if we consider the meaning of kāś “to shine, be brilliant, have an agreeable appearance” (MW, s.v.). We also know that Tibetan orthographies, particularly at the early phases of the development of Tibetan script and literature, were not standardised. Well, this is the extent to which I can go at the moment.
PS. In the mean time some colleagues have pointed out to the occurrences of ’drob skyong in Tibetan canonical sources.