The affixes yañ and añ come respectively in the sense of 'its product' after the words 1. kaṃsīya and 2. paraśavya and there is luk elision (of the cha and yat affixes of those words).,
The word कंसीयः is formed by छ 5.1.1, and परशव्य is formed by adding यत् 5.1.2. These affixes छ and यत् are elided when the affixes यञ् and अञ् are added. Thus कंसीय + यञ् = कंस + यञ् = कांस्यः so also पारशव from परशव्य thus परशव्य + अञ् = परशु + अञ् = पारशवः ॥
The words लुक् च mean 'there shall be elision'. Of what? Certainly not of the primitive, for लुक् is never applied to the elision of a base, but of an affix only 1.1.61. It follows therefore that the elision is of the affixes of कंसीय and परशव्य ॥ Now these words have two affixes, thus. To the root कम् is added first the Unadi affix स (Un III. 62) and we get कंस; next to कंस is added छ. So also to पर + शृ is added the affix उ (Un I. 33) and we have परशु, to which is then added यत् and we have परशव्य ॥ The question arises, should these affixes स and उ be also elided. The answer is 'no'. The word प्रातिपदिकात् of 4.1.1 is understood is this sutra; so the elision will take place of those affixes only which follow a pratipadika. But स and उ are added to a Dhatu and not a pratipadika, hence those affixes are saved from the operation of लुक् ॥
The word परशव्य being gravely accented on the first 6.1.185 would have taken अञ् by 4.3.140. The present sutra teaches the elision only of its affix यत्, अञ् being already obtained.
Q. The final अ of कंसीय and परशव्य will be elided by 6.4.148 before these taddhita affixes, and after such elision, the final य् will be elided by 6.4.150, where is then the necessity of this sutra?
A. The final य् will not be elided, because 6.4.150 will apply only then, when an affix beginning with long ई follows, which is not the case here.,