deriv SD cv (879) ashtadhyayi.com hei.de L 879 ETT STT a 7.4.46 ALPH OLDHOMEPAGE NEWHOMEPAGE

do dad ghoH दो दद्घोः ONPANINI 74046

Replace the da द of a /ghu with dath दथ् (before a /kit t त् affix).

dA दा + /kta → dath दथ् + ta त → !**datta- दत्तॱ

Why do we say "of a /ghu"?

The dAp that means "cut" is not a /ghu —

dAtam barhiH दातं बर्हिः

How do you know that the sUtra has dath दथ् and not dad दद्, dat दत् or dadh दध्? By jhalAJjazonte, any of those would make dadghoH दद्घोः.

There's a stanza that answers that —

tAnte dIrghatvAkhyo doSo dAnte doSo niSThAnatvam |
तान्ते दीर्घत्वाख्यो दोषो दान्ते दोषो निष्ठानत्वम्।
dhAnte doSo dhatvAkhyas syAn nirdoSatvAt thAnto grAhyaH ||
धान्ते दोषो धत्वाख्यः स्यान्निर्दोषत्वात्थान्तो ग्राह्यः ॥

candravasu translates it.