Valmiki Ramayana Yuddha Kanda Sarga 99 Shloka 18
Original Shlokaतंम्तैलधौतंविमलंशैलसारमयंदृढम् ।।6.99.18।। राक्षसःपरमक्रुद्धोवालिपुत्रेन्यपातयत् ।
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परमक्रुद्धः extremely enraged, राक्षसः Rakshasa, तैलधौतम् smeared with oil, विमलम् clean, शैलसारमयम् like feet of mountain, दृढम् strong, तंम् that, वालिपुत्रे Vali's son, न्यपातयत् hurled
Extremely enraged Rakshasa, hurled at Vali's son that axe that was cleansed with oil, the clean strong axe that was like feet of a mountain.