Valmiki Ramayana Yuddha Kanda Sarga 56 Shloka 21
Original Shlokaतंगृहीत्वामहास्कन्धंसोऽश्वकर्णंमहाद्युतिः । प्रहस्यपरयाप्रीत्याभ्रामयामासभूतले ।।6.56.21।।
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महाद्युतिः endowed with great splendour, सः he, महास्कन्धम् with huge trunk, अश्वकर्णम् Aswakarana tree, गृहीत्वा seizing, परया great, प्रीत्या with delight, प्रहस्य laughing, भूतले on the ground, भ्रामयामास whirled it round.
He (Hanuman) endowed with great splendour, seizing a huge trunk of Aswakarana tree with great delight, whirled it round on the ground laughing.