Valmiki Ramayana Yuddha Kanda Sarga 74 Shloka 46
Original Shlokaपद्भ्यांतुशैलमापीड्यबडबामुखवन्मुखम् । विवृत्योग्रंननादोच्चैस्त्रासयन्निवराक्षसान् ।।6.74.46।।
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शैलम् mountain, पद्भ्याम् by feet, आविध्य pressing, बडबामुखवत् opening his largemouth, उग्रम् angry, मुखम् face, विवृत्य opening, इवराक्षसान् like Rakshasas, त्रासयन् fearful, उच्चैः loudly, ननाद roared.
Pressing the mountain hard by his feet, opening his largemouth wide, he roared like Rakshasas to make Rakshasas fearful.