Valmiki Ramayana Ayodhya Kanda Sarga 14 Shloka 23
Original Shlokaस नुन्न इव तीक्ष्णेन प्रतोदेन हयोत्तमः। राजा प्रचोदितोऽभीक्ष्णं कैकेयीमिदमब्रवीत्।।2.14.23।।
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सः राजा that king (Dasaratha), तीक्ष्णेन with a sharp, प्रतोदेन by the lash, नुन्नः beaten up, हयोत्तमः इव like a horses of the best breed, अभीक्ष्णम् exceedingly, प्रचोदितः incited, कैकेयीम् to Kaikeyi, इदम् this word, अब्रवीत् said.
The king who was very much incited by her words, like a horse of the best breed whipped by the lash, replied to Kaikeyi: