मयतेरिदन्यतरस्याम्

Operational rule vidhi

इ may optionally be substituted for the आ of मा (मयति) before ल्यप् .

Word by word (padaccheda)

Target मयतेः ṣaṣṭhī · ekavacanaSubstitute / term prathamā · ekavacanaRight context अन्यतरस्याम् saptamī · ekavacana

Target Ṣaṣṭhī (6th case): names what gets replaced, "in place of X" (1.1.49 षष्ठी स्थानेयोगा).
Substitute / term Prathamā (1st case): in operational rules, the substitute or the thing introduced; in definitions, the term or its referent.
Right context Saptamī (7th case): "when X follows", the operation applies to what precedes (1.1.66 तस्मिन्निति निर्दिष्टे पूर्वस्य). Also a condition or domain ("in the sense of").

Dotted words are technical terms. Hover or tap one to see its card.

मयतेः अन्यतरस्याम्

Pāṇini leaves out words that carry over from earlier sūtras. Expand to see the rule as a reader actually understands it.

As a rewrite rule (sketch from case endings)

मयतेः → / अन्यतरस्याम्

Replace mayateḥ with it when anyatarasyām follows. Inherited words (anuvṛtti) may add further conditions.

इ may optionally be substituted for the आ of मा (मयति) before ल्यप् ।
Thus अपमित्य or अपमध्य ॥

Śrīśa Chandra Vasu, The Ashtadhyayi of Panini (1897), via ashtadhyayi.com.