Valmiki Ramayana Aranya Kanda Sarga 51 Shloka 42
Original Shlokaतस्य व्यायच्छमानस्य रामस्यार्थे स रावणः।।3.51.42।। पक्षौ पार्श्वौ च पादौ च खड्गमुद्धृत्य सोऽच्छिनत्।
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सः that, रावणः Ravana, खडगम् sword, उद्यम्य after lifting, रामस्य Rama's, अर्थे for the sake of, व्यायच्छमानस्य of one who was fighting relentlessly, तस्य his, पक्षौ two wings, पार्श्वौ च both sides, पादौ च feet, अच्छिनत् cut off.
Ravana lifted his sword and cut off both the wings and feet of Jatayu who was fighting relentlessly (for Rama's sake).