Valmiki Ramayana Yuddha Kanda Sarga 57 Shloka 41
Original Shlokaनिर्याणश्रीश्चयाऽस्यासीद्भास्वरावसुदुर्लभाः । साननाशमुहूर्तेनसमेचस्खलिताहयाः ।।6.57.41।।
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भास्वरा splendour, वसुदुर्लभा that which is difficult, या for, निर्याणश्री disappeared, सा that, मुहूर्तेन moment, ननाश destroyed, हयाश्च even horses, समे even ground, स्खलिताः stumbled.
The splendour of Prahastha which is difficult to destroy, disappeared at that moment and the horses stumbled on even ground.