Valmiki Ramayana Yuddha Kanda Sarga 93 Shloka 16
Original Shlokaएवमादिविलापार्तंरावणंराक्षसाधिपम् ।।6.93.16।। आविवेशमहान् कोपःपुत्रव्यसनसम्भवः ।
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एवमादिविलापार्तम् lamenting in this way, distressed, राक्षसाधिपम् Rakshasa king, रावणम् Ravana, पुत्रव्यसनसम्भवः sorrow of son deserting, महान् very कोपः angry, अविवेश took over
Distressed Ravana was lamenting in this way on account of his son deserting, as anger had taken over him.