Valmiki Ramayana Yuddha Kanda Sarga 71 Shloka 43
Original Shlokaतत् त्सैन्यंहरिवीराणांत्रासयामासराक्षसः । मृगयूथमिवक्रुद्धोहरिर्यौवनदर्पितः ।।6.71.43।।
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यौवनदर्पितः lion with youthful pride, राक्षसः Rakshasa, क्रुद्धः enraged, हरिः monkey, मृगयूथमिव group of deer, हरिवीराणाम् monkey heroes, तत् that, सैन्यम् army, त्रासयामास struck.
Just as a young lion with youthful pride would strike a group of deer, the enraged Rakshasa struck the army of monkey heroes.