359. Adjective compounds from these words are very few; those which occur are declined like the simple stems: thus, híraṇyavāçīs and sahásrastarīs, átaptatanūs and sárvatanūs, all nom. sing. masculine.
Stems ending in diphthongs.
360. There are certain monosyllabic stems ending in diphthongs, which are too few and too diverse in inflection to make a declension of, and which may be most appropriately disposed of here, in connection with the stems in ī and ū, with which they have most affinity. They are:
a. stems in āu: nāú and glāú;
b. stems in āi: rāí;
c. stems in o: gó and dyó (or dyú, dív).
361. a. The stem nāú f. ship is entirely regular, taking the normal endings throughout, and following the rules for monosyllabic accentuation (317) — except that the accus. pl. is said (it does not appear to occur in accented texts) to be like the nom. Thus: nāús, nā́vam, nāvā́, nāvé, nāvás, nāví; nā́vāu, nāubhyā́m, nāvós; nā́vas, nā́vas, nāubhís, nāubhyás, nāvā́m, nāuṣú. The stem glāú m. ball is apparently inflected in the same way; but few of its forms have been met with in use.
b. The stem rāí f. (or m.) wealth, might be better described as rā with a union-consonant y (258) interposed before vowel endings, and is regularly inflected as such, with normal endings and monosyllabic accent. Thus: rā́s, rā́yam, rāyā́, rāyé, rāyás, rāyí; rā́yāu, rābhyā́m, rāyós; rā́yas, rāyás, rābhís, rābhyás, rāyā́m, rāsú. But in the Veda the accus. pl. is either rāyás or rā́yas; for accus. sing. and pl. are also used the briefer forms rā́m (RV. once: rā́yam does not occur in V.) and rā́s (SV., once); and the gen.-sing. is sometimes anomalously accented rā́yas.
c. The stem gó m. or f. bull or cow is much more irregular. In the strong cases, except accus. sing., it is strengthened to gāú, forming (like naú) gāús, gā́vāu, gā́vas. In accus. sing. and pl. it has (like rāí) the brief forms gā́m and gā́s. The abl.-gen. sing. is gós (as if from gu). The rest is regularly made from go, with the normal endings, but with accent always remaining irregularly upon the stem: thus, gávā, gáve, gávi, gávos, gávām; góbhyām, góbhis, góbhyas, góṣu. In the Veda, another form of the gen. pl. is gónām; the nom. etc. du. is (as in all other such cases) also gā́vā; and gā́m, gós, and gā́s are not infrequently to be pronounced as dissyllables. As acc. pl. is found a few times gāvas.
d. The stem dyó f. (but in V. usually m.) sky, day is yet more anomalous, having beside it a simpler stem dyu, which becomes div before a vowel-ending. The native grammarians treat the two as
