Valmiki Ramayana Aranya Kanda Sarga 27 Shloka 10
Original Shlokaस सम्प्रहारस्तुमुलो रामत्रिशिरसोर्महान्। बभूवातीव बलिनोस्सिंहकुञ्जरयोरिव।।3.27.10।।
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रामत्रिशिरसोः between Rama and Trisira, तुमुलः tumultuous, महान् great, सः सम्प्रहारः that fight, अतीव very, बलिनोः strong ones, सिंहकुञ्जरयोः इव as between a lion and an elephant, बभूव took place.
The tumultuous combat between Rama and Trisira looked like the strong fight between a lion and an elephant.