Karnatakabhashabhushana 6.12

[6.12] There is elision of that which begins with the penultimate vowel of a prior member having a substantive as posterior member.

Of a prior member standing in the form of a qualifier whose posterior member is a substantive, there is elision of the part beginning with the penultimate vowel.

kārmaḍu

kūrvāḷ

immāvu

innuṇisu

nuṇbaraṁ

oḷvātu

oḷguṇaṁ

oḷnuḍi;

oḷvānasaṁ.