Game 15

Question:

रात्रौ अस्ति न दिवसे रामे अस्ति न लक्ष्मणे ।

स्वरे अस्ति न व्यञ्जने यदि जानासि तद्वद ॥

raatrau asti na divase raame asti na lakShmaNe |

svare asti na vya~njane yadi jaanaasi tadvada ||

Exposition:

Solve this प्रहेलिका (prahelikaa - riddle).

After splitting the composite words (sandhis), it could be read as -

रात्रौ अस्ति न दिवसे रामे अस्ति न लक्ष्मणे ।

स्वरे अस्ति न व्यञ्जने यदि जानासि तत् वद ॥

raatrau asti na divase raame asti na lakShmaNe |

svare asti na vya~njane yadi jaanaasi tat vada ||

Meaning:
It is in night (रात्रि, raatri) and not in day (दिवस, divasa).  It is in Raama (राम) and not LakShmaNa (लक्ष्मण).  It is in vowel (स्वर, swara) not in consonent (व्यञ्जन. vya~njana). If you know it, say it!

Answer:
This is an Antarlāpikā (अन्तर्लापिका) riddle. The answer is hidden inside the verse itself, within the description.

Upon examining the words given in Sanskrit, it becomes evident that the common factor in all the 3 words - रात्रि, राम, and स्वर is the syllable - 

रेफ

repha 

the syllable 'ra'

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