Valmiki Ramayana Yuddha Kanda Sarga 14 Shloka 4
Original Shlokaयावन्नगृह्णन्तिशिरांसिबाणारामेरिताराक्षसपुङ्गवानाम् । वज्रोपमावायुसमानवेगाःप्रदीयतांदाशरथायमैथिली ।।6.14.4।।
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वज्रोसमाः equal to thunderbolt, वायुसमानवेगाः speed of wind, रामेरिताः released by Rama, बाणाः arrows, राक्षसपुङ्गवानाम् leaders of Rakshasas, शिरांसि: heads, यावत् l, नगृह्णन्ति: take away, मैथिली: Mythili, दाशरथाय: to Rama son of Dasaratha, प्रदीयताम् give away.
"Give away Mythili to Rama before he releases arrows like that of thunder bolt with the speed of wind and take away the heads of the leader."