Valmiki Ramayana Yuddha Kanda Sarga 104 Shloka 3
Original Shlokaखराश्चखरनिर्घोषागगनेपरुषाघनाः । औत्पातिकानिनर्दन्तस्समन्तात्परिचक्रमुः ।।6.104.3।।
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खराः donkeys, खरनिर्घोषाः emitting harsh sound, परुषाः dreadful, औत्पातिकानि portentous, घनाः clouds, गगने in the sky, समन्तात् all over, परिचक्रमुः went round
Dreadful and portentous clouds went in circles all over sky looking like donkeys emitting harsh sounds.