Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 34
Original Shlokaतस्य लाङ्गूलमाविद्धमात्तवेगस्य पृष्ठतः। ददृशे गरुडेनेव ह्रियमाणो महोरगः।।5.1.34।।
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आत्तवेगस्य of great, तस्य his, पृष्ठतः at the back, अविद्धम् curled, लाङ्गूलम् tail, गरुडेन by Garuda, ह्रियमाणः carried off, महोरगः इव like a big serpent, ददृशे appeared.
Hanuman had the tail curled at his back which appeared like a big serpent being carried off by Garuda.