Valmiki Ramayana Sundara Kanda Sarga 22 Shloka 23
Original Shlokaसीताया वचनं श्रुत्वा रावणो राक्षसाधिपः। विवृत्य नयने क्रूरे जानकीमन्ववैक्षत।।5.22.23।।
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राक्षसाधिपः lord of demons, रावणः Ravana, सीतायाः Sita's, वचनम् words, श्रुत्वा on hearing, क्रूरे cruel ones, नयने eyes, विवृत्य turning them dreadfully, जानकीम् at Janaki, अन्ववैक्षत looked at.
On hearing Janaki, the lord of demons, Ravana looked at her with his cruel eyes opened wide and rolling.