Valmiki Ramayana Aranya Kanda Sarga 52 Shloka 17
Original Shlokaतस्याः कौशेयमुद्धूतमाकाशे कनकप्रभम्। बभौ चादित्यरागेण ताम्रमभ्रमिवातपे।।3.52.17।।
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तस्याः her, आकाशे in the sky, उद्धूतम् blown by the wind, कनकप्रभम् goldenhued, कौशेयम् silken robes, आतपे exposed to the evening Sun , आदित्यरागेण by the Sun's redness, ताम्रम् red, अभ्रमिव cloudlike, बभौ appeared.
As the goldencoloured garment worn by Sita blew in the wind, it looked like a coppercoloured cloud illumined by the evening Sun in the sky.