In the chandas (Vedas), both ru and r are substituted for the final 1. amanas 2. ūdhas and 3. avas,
Thus अम्न एव or अम्नरेव, ऊध एव or ऊधरेव; अव एव or अवरेव ॥ When रु is substituted for the finals, this रु is replaced by य् by 8.3.17, which is elided by 8.3.19. The word अम्नस् means 'a little', and अवस् 'protection'.
Vart:- रु and र both replace the final of प्रचेतस् before राजन्, in the Vedic as well as in the secular language. As प्रचेता राजन् 8.3.14, 6.3.111 प्रचेतो राजन् ॥
Vart:- The words अहर् &c before पति &c should be enumerated. That is, the finals of अहर् &c are replaced by रु or र before पति &c. As. अहर्पतिः or अहᳶपतिः or अहः पतिः, अहर्पुत्रः, अहᳶपुत्रः, अहः पुत्रः, गीर्पतिः, गीः पति, गीᳶपतिः; धूर्पति, धूः पतिः, धूᳵपतिः ॥ Here र् is substituted for the final र् of अहर् &c, which at first sight may appear superfluous. But it is so ordained, in order to prevent the visarga change of this र ॥,