Valmiki Ramayana Aranya Kanda Sarga 31 Shloka 23
Original Shlokaअसाध्यः कुपितो रामो विक्रमेण महायशाः। आपगायास्सुपूर्णाया वेगं परिहरेच्छरैः।।3.31.23।।
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महायशाः man of great fame, रामः Rama, विक्रमेण in valour, असाध्यः irrepressible, कुपितः when outraged, सुपूर्णायाः in full spate, आपगायाः of a river, वेगम् speed, शरैः with arrows, परिहरेत् he may arrest.
Rama is of great fame. When outraged, he is irrepressible. He can arrest with his arrows even the speed of a river (in spate).