Valmiki Ramayana Yuddha Kanda Sarga 4 Shloka 109
Original Shlokaतेषां निविशमानानां सैन्यसन्नाहनिस्स्वनः । अन्तर्धाय महानादमर्णवस्य प्रशुश्रुवे ।।6.4.109।।
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तेषाम् by their, निविशमानानाम् quartering there, सैन्यसन्नाहनिस्स्वनः by the assembly of the army, अर्णवस्य of the ocean, महानादम् great noise, अन्तर्धाय drowning, प्रशुश्रुवे that which was produced
The noise of the ocean was drowned by the great sound produced by the assembly of the army quartered there.