Valmiki Ramayana Yuddha Kanda Sarga 66 Shloka 2
Original Shlokaननाद च महानादंसमुद्रमभिनादयन् । विजयन्निवनिर्घातन्विधमन्निवपर्वतान् ।।6.66.2।।
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निर्घातान् bringing out loud noise,विजयत्रि as if proclaiming victory, पर्वतान् mountains, विधमन् इव like breaking, महानादम् great sound, समुद्रम् ocean, अभिनादयन् reverberate, नादयन roared.
Kumbhakarna roared making loud noises as if proclaiming victory, like the breaking of mountains and reverberating of ocean.