Valmiki Ramayana 6.74.46

पद्भ्यां तु शैलमापीड्य वडवामुखवन्मुखम्।विवृत्योग्रं ननादोच्चैस्त्रासयन्निव राक्षसान्॥

padbhyāṃ tu śailamāpīḍya vaḍavāmukhavanmukham |vivṛtyograṃ nanādoccaistrāsayanniva rākṣasān ||

Our plain-language meaning of this verse is waiting for scholar review.