deriv SD cv (194) ashtadhyayi.com hei.de L 194 ETT STT a 7.3.119 ALPH OLDHOMEPAGE NEWHOMEPAGE

ac ca gheH अच्च घेः ONPANINI 73119

The final i इ u उ of a /ghi, together with /Gi, make au औ.

Examples:

**agni- अग्निॱ m + /Gi → !**agnau अग्नौ "on the fire"

**RSi- ऋषिॱ m + /Gi → !**RSau ऋषौ "about the seer"

**mati- मतिॱ f + /Gi → !**matau मतौ "in (someone's) opinion"

**vanaspati- वनस्पतिॱ m + /Gi → **vanaspatau वनस्पतौ "on a tree"

**guru- गुरुॱ m + /Gi → !**gurau गुरौ "about teacher"

Why "of a /ghi"?

Because /sakhi- and uncompounded /pati- are not /ghi, so their i इ stays —

/sakhi- m + /Gi
→ /sakhi- + au औ by < aut
→ !**sakhyau सख्यौ by ikoyaNaci

/pati- m + /Gi
→ /pati- + au औ by < aut
→ !**patyau पत्यौ

Also, feminines in i इ u उ, before /Gi, may be non-/ghi optionally by Gitihrasvazca. So when we take that option and **mati- मतिॱ f becomes /nadI —

**mati- मतिॱ f + /Gi → **matyAm मत्याम्

How is the original sUtra worded?

(Before /Gi,) replace /ghi bases with a अ (and the /Gi with au औ).

Example:

RSi- ऋषिॱ m + /Gi
→ RSa- ऋषॱ + /au, replacing both at the same time by this rule
→ **RSau ऋषौ "about seer" by vRddhireci

Why is there a "/ca" in the sUtra?

To debar John's blanket principle, thusly inheriting "and the /Gi with au औ" from < aut.

It's stupid for this sUtra to make an a अ that rule vRddhireci will always eat up straight away. Why didn't /pANini just say "replace with /lopa" instead of "replace with a अ"?

Because, though "replace with /lopa" and "replace with a अ" both work, sUtras have to be ASHAP. Your wording "lopazcagheH लोपश्चघेः" would have been too longwinded.