A feminine word not ending in the affix ūṅ and having an equivalent and uniform masculine is changed into such masculine form, before the affixes beginning with tasil etc. -- pañcamyāstasil [[5.3.7]], and ending with kṛtvasuc -- saṃkhyāyāḥ kriyā'bhyāvṛttigaṇane kṛtvasuc [[5.4.17]].,
Thus तस्याः शालायाः = ततः, तस्यां = तत्र, यस्यां = यत्र, यस्या = यतः ॥ The following are the affixes before which the feminine is changed to masculine: त्र and तस्, तरप् and तमप्, चरट्, जातीयर्, कल्पप्, देश्य, देशीयर् रूपप्, पाशप्, थम, थाल, दा and र्हिल तिल् तातिल् ॥ All other affixes do not affect the gender. Thus तरप् तमप् &c दर्शनीयतरा, दर्शनीयतमा, पटुचरी, पटुजातीया, दर्शनीयकल्पा, दर्शनीयदेशीया, दर्शनीयरूपा, दर्शनीयपाशा ॥ कया प्रकृत्या = कथम्, यया प्रकृत्या = यथा, तस्यां वेलाया = तदा, तर्हि &c.
Vart:- The feminine of बहु and अल्प is changed to masculine before the Taddhita affix शस्ः- as बह्वीभ्यो देहि = बहुशो देहि; अल्पाभ्यो देहि = अल्पशो देहि ॥
Vart:- A feminine Adjective is changed into masculine before the affixes त्व and तल् ॥ As पट्व्या भावः = पटुत्वम् or पटुता ॥ Why do we say 'an adjective'? Observe कठ्या भावः = कण्ठीत्वं or कठीता ॥
Vart:- The feminine word is changed to masculine before all Taddhita affixes, except ड, when the word gets the designation of भ ॥ Thus हस्तिनीनां समूहः =हास्तिकम् ॥ Had the word not become masculine, then हस्तिनी having lost its ई 6.4.148, the word न् of हस्तिन् the would not be elided before the Taddhita affix, because the lopa-elision being sthanivat, would have prevented the application of the rule 6.4.144, ordaining the elision of the final syllable. So the form would have been something like हास्तिनिकम् instead of हास्तिकम् ॥ Why do we say 'with the exception of ड'? Observe श्यैनेयः, रौहिनेयः the masculine being श्येत and रोहित ॥ The word आग्नेयः (= अग्नायी देवता अस्य स्थालीपाकस्य) is an exception to this rule.
Vart:- The masculine-change takes place before the affixes ठक् and छस् ॥ As भवत्या श्छात्रा = भावस्काः, भवदीयाः ॥,