Valmiki Ramayana Yuddha Kanda Sarga 37 Shloka 18
Original Shlokaएकैकस्यात्रयुद्धार्थेराक्षसस्यविशाम्पते । परीवारस्सहस्राणांसहस्रमुपतिष्ठते ।।6.37.18।।
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विशाम्पते Lord of men, अत्र there, एकस्य for one, राक्षसस्य Rakshasa, युद्धार्थे to assist in war, सहस्राणाम् thousands of, सहस्रम् thousands, परीवारः at the service, उपतिष्ठते are staying.
"O! Lord of men! For the sake of assisting one Rakshasa in war ten lakhs of Rakshasas are staying at his service."