Valmiki Ramayana Sundara Kanda Sarga 26 Shloka 29
Original Shlokaनूनं लङ्का हते पापे रावणे राक्षसाधमे। शोषं यास्यति दुर्धर्षा प्रमदा विधवा यथा।।5.26.29।।
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पापे when the sinner, राक्षसाधमे mean demons, रावणे when Ravana, हते is killed, दुर्धर्षा impregnable, लङ्का Lanka, नूनम् surely, विधवा widow, प्रमदा यथा like a woman, शोषम् wither up, यास्यति truly.
"Surely this impregnable Lanka will wither up (lose its splendour) and appear like a widow when this sinful Ravana, a mean demon is killed.