Valmiki Ramayana Sundara Kanda Sarga 18 Shloka 30
Original Shlokaरावणोऽयं महाबाहुरिति सञ्चिन्त्य वानरः। अवप्लुतो महातेजा हनुमान्मारुतात्मजः।।5.18.30।।
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मारुतात्मजः son of the Windgod, वानरः vanara, महातेजाः brilliant one, हनुमान् Hanuman, अयम् this, महाबाहुः strongarmed, रावणः Ravana, इति this, सञ्चिन्त्य having thought, अवप्लुतः got down.
The brilliant vanara (Hanuman), son of the Windgod recognising the strongarmed Ravana got down a little, saying 'This is truly the strongarmed Ravana.'