Valmiki Ramayana Yuddha Kanda Sarga 70 Shloka 41
Original Shlokaतःखडगंसमुद्यम्यत्रिशिराराक्षसोत्तमः । निजघानतदाव्यूढेवायुपुत्रस्यवक्षसि ।।6.70.41।।
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राक्षसोत्तमः foremost of Rakshasas, त्रिशिराः Trisira, ततः that, व्यूढं placed, समुद्यम्य lifting up, तदा then, खडगम् sword, वायुपुत्रस्य into son of wind god, वक्षसि chest of, निजघा dug into.
Trisira, the foremost of Rakshasas then lifted his sword, placed it on the chest of Hanuman and dug into it.