A master philologist is a like a master detective. I cannot claim to be a master philologist but like any philologist or a detective, I believe to have a case and I believe to have solved it. I wonder if and how convincing my solution may seem to other philologists. At least, let us say, I have a hypothesis.
Of the four or five Indian commentaries in Tibetan translation on the Bhadracarī, the *Bhadracarīpraṇidhānarājaṭīkā is ascribed to one Indian author whose Sanskrit name has been rendered into Tibetan as “rGyan bzang po.” Whether he and Śākyamitra each composed a separate ṭīkā or whether they co-authored one ṭīkā seems worth investigating. But this issue is not significant for my present case. The issue that concerns me here is what could have been the Sanskrit name of “rGyan bzang po.” To be sure, the name in Tibetan is well attested in some of the earliest catalogues and other textual witnesses and hence it is not an issue here. Already in 1912, in his German dissertation on the Bhadracarī, Kaikioku Watanabe (Watanabe 1912: 23), reconstructed the name as “(Vi)bhūṣaṇabhadra” or Alaṃkārabhadra.” But like any good philologist, he was cautious. He conceded: “The exact form of the name of the composer remains unsettled because it is otherwise unknown” (Die genaue Form des Verfassernamens bleibt unbestimmt, weil er sonst unbekannt ist). Dan Martin in his Tibskrit has reconstructed “rGyan bzang po” as *Subhūṣita. However, in the same Tibskrit, Martin records “Bhadrapaṇa” to which he adds “Author of a commentary on the Bzang po spyod pa’i smon lam. It’s listed as no. 5515 in the Peking Tanjur. Schaik, Prayer, p. 185” (i.e. van Schaik 2009: 185). But actually in Herrmann-Pfandt 2008: 319, the bZang po spyod pa’i smon lam (P 5515) in question here has already been identified as the *Bhadracarīpraṇidhānarājaṭīkā by “rGyan bzang po.” The Sanskrit name of the author is given as Bhadrāpaṇa in Herrmann-Pfandt 2008: 319. There is a remark in German (“Identifikation eindeutig”). But there is no remark to the name of the author. The bilingual name has been indexed (pp. 466, 472) and the orthography of the name in Sanskrit is consistently “Bhadrāpaṇa.”
The question now is how can we explain the Sanskrit–Tibetan correspondence of the name. There is no difficulty with bhadra and bzang po. It has been presupposed that bhadrāpaṇa = bhadra + āpaṇa. The second component of the name cannot possibly be apaṇa. But can āpaṇa mean rgyan? According to MW (s.v. āpaṇa), it can mean “a market, a shop,” “waves” or “commerce, trade” (only in lexicons with no real usage). But there seems to be no element of Tibetan rgyan in this word. And more importantly, does the Tibetan word really mean “ornament” or “ornamented” as the earlier attempts of reconstruction presupposed? But before we answer this, let us consider the orthography “Bhadrapaṇa” that Martin gives based on van Schaik 2009: 185. And what does paṇa mean? According to MW (s.v. paṇa), it can mean “paṇa m. (ifc. f(ā).) play, gaming, playing for a stake, a bet or a wager (with gen.; loc. or ifc.; paṇaṃ√kṛ, to make a bet; paṇe ni√as, to stake at play),” “the thing staked or the sum played for, wages, hire, reward.” But would such a meaning agree with the meaning of the Tibetan word rgyan? Yes, it would. According to Jäschke 1881 (s.v. rgyan, II1–2), rgyan can, as a noun, mean “a stake or pledge at play” and “lot” and in the verbal construction (as in rgyan btsugs/rgyab) it could mean “to bet” or “to wedger.” This is also confirmed by the Tshig mdzod chen mo (s.v. rgyan 2): rgyal dang skugs, ... sho sbag brgyab nas rgyan rgyal ba, ... dngul zong ci rigs kyi rgyan ’gyed pa, ... shing bu dang, rde’u sogs bsgrugs te rgyan rgyag pa, ... rgyal pham thob shor gyi ched du rgyan ’phen pa, ... rtsed mo thob shor gyi ched du dngul ’bor chen rgyan du btsugs pa. Thus the word rgyan in the name “rGyan bzang po” must mean something like “bet” or “lot,” and the Sanskrit name, with great probability, had been “Bhadrapaṇa,” and meant something like “Good Bet” or “Good Lot.”