A word in the genitive case is not compounded with another, when the force of the sixth case-affix is that of specification (nirdhāraṇa).,
With this sutra, begins a series of exceptions to the composition of words in the genitive case. The separation of one from the many, on account of its genus, attribute and action, is called 'nirdharana.' As क्षत्रियो मनुष्याणां शूरतमः 'the Kshatriya is the most powerful amongst men.' कृष्णा गवां संपन्नक्षीरतमः 'the black cow is the most milk-giving amongst cows.' धावन्नधगानां शीघ्रतमः 'the runner is the swiftest amongst walkers.' This form of genitive meaning 'amongst,' is ordained by sutra 2.3.41.
Vart:- A word taking a genitive-case by force of any rule other than sutra 2.3.50, is never compounded. See sutra 8. Thus the following words are never compounded सर्पिषोज्ञानम् , मधुनोज्ञानम्.,