In the chandas (Vedas) the affix amu (am) also is added after the above, under similar circumstances.,
To the word किम्, words ending in ए, finite verbs and indeclinable, when taking the comparative affixes तर and तम is added the affix अम् in the Vedas, when these words are used as adverbs. By the force of the word च 'also' in the sutra, the affix आमु is also included. Thus प्रतरम् नयामः ॥ or प्रतराम् वस्यः । प्रतर means प्रकृष्टतर ॥
The words ending in आम् and अम् are indeclinables as they are included in the class of Svaradi (1. 1.37).,