अवयाः श्वेतवाः पूरोडाश् च

The word अवयाः is from अव + यज्; श्वेतवाः from श्वेत + वह्, and पुरोडाः from पुरस् + दाश् ॥ The affix ण्विन् is added to the two latter by 3.2.71. The word अवयाज् is also formed by ण्विन् 3.2.72. Thus the three words श्वेतवाह्, पुरोडाश् and अवयाज् are formed. These words take the affix डस् before the Pada-terminations (See Vartika to 3.2.71). After having taken डस्, the above forms अवयाः &c., are made in Nominative singular irregularly.

Why is this nipatana, when रु would have come by the last sutra_ and the lengthening would have taken place by 6.4.14, of the words अवयस्, श्वेतवस् and पुरोडस्? They are so exhibited here, for making them long in the Vocative singular also. For they could not have been lengthened in the Vocative singular, because 6.4.14 does not apply to it. Thus हे अवयाः, हे श्वेतवाः, हे पुरोडाः ॥

The word च shows that other forms, not enumerated, may also be included here under. As हे उक्थशाः ॥,