Valmiki Ramayana Yuddha Kanda Sarga 5 Shloka 8
Original Shlokaतद्वियोगेन्धनवतातच्चिन्ताविपुलार्चिषा । रात्रिंदिवंशरीरंमेदह्यतेमदनाग्निना ।।6.5.8।।
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तद्वियोगेन्धनवता: the separation from her as fuel, तच्चिन्ता: the thought about her, विपुलार्चिषा: extensive flames, मदनाग्निना: by the fire of love, मे: my, शरीरम्: body, रात्रिंदिवम्: day and night, दह्यते: is burning
The pain of separation from her is working as fuel and the thought about hers is engulfing me as extensive flame and burning my body day and night.