The following names are irregularly formed 1. āsandīvat 2. aṣṭhīvat 3. cakrīvat 4. kakṣīvat 5. rumaṇvat and 6. carmaṇvatī (Reference śloka - āsandīvati dhānyādaṃ rukmiṇaṃ haritasrajam aśvaṃ babandha sāraṅgaṃ devebhyo anamejayaḥ),
The change of म् to व् in these was obtained from the last sutra. The irregularity consists in the substitutions of stems. आसन्दीवत्, is from the stem आसन which is here changed to आसन्दी ॥ As आसन्दीवान् ग्रामः, आसन्दीवद् अहिस्थलम् ॥ As in the following sloka :
आसन्दीवति धान्यादं रुक्मिणं हरितस्रजम् ।
अश्वं बबन्ध सारङ्गं देवेभ्यो जनमेजयः ॥
When not a name, we have आसनवान् ॥ Others say, that there is a separate and distinct stem आसन्दी, as in the sentence औदुम्बरी राजासन्दी भवति ॥ The change of म् to व् after this word would take place regularly by the last sutra: its mention here, according to these authors, is merely explanatory. 2. अष्ठीवत् is from अस्थि which is changed to अष्ठी ॥ As अष्ठीवान् the name of a particular portion of body; the knee-joints. Otherwise अस्थिवान् ॥ 3. चक्रीवत् is from चक्र which is changed to चक्री, as चक्रीवान् राजा ॥ Otherwise we have चक्रवान् ॥ चक्रीवन्ति सदोहविर्द्धामानि भवन्ति is a Vedic example. It means सारस्वते सत्रेजङ्गमानि सदो हविर्धानानि, न त्वेकत्रावस्थितानि, तानि तत्र तत्र कर्षणाय चक्रयुक्तानि भवन्ति ॥ 4. कक्षीवत् is from कक्ष्या, there is vocalisation of य and the lengthening is by 6.4.2. कक्षीवान् is the name of a Rishi. Otherwise we have, कक्ष्यावान् ॥ 5. रुमण्वत् is from लवण which is changed to रुमण् ॥ Otherwise we have लवणवान् ॥ Others say, that there is a distinct word रुमन्, and the न् is not elided, but changed to ण् ॥ Or that the affix मत् takes the augment नुट् ॥ 6. चर्मण्वती is from चर्मन्, there is non-elision of न् and its change to ण् ॥ Or मत् has taken नुट् augment. The Charmanvati is the name of a river. Otherwise we have चर्मवती ॥,