Valmiki Ramayana Yuddha Kanda Sarga 90 Shloka 24
Original Shlokaस सम्प्रहारस्तुमुलःसञ्जज्ञेकपिरक्षसाम् ।।6.90.24।। देवासुराणांक्रुद्धानांयथाभीमोमहास्वनः ।
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कपिरक्षसाम् Vanaras and Rakshasas, सः they, तुमुलः vehement, महास्वनः in loud clamour, भीमः fearful, सः they, सम्प्रहार battle, क्रुद्धानां enraged, देवासुराणांयथा like the battle of Devas and asuras, सञ्जज्ञे took place
Fearful and vehement battle took place between enraged Vanaras and Rakshasas making loud clamours like the battle (in the past) between Devas and asuras.