Valmiki Ramayana Yuddha Kanda Sarga 60 Shloka 56
Original Shlokaसनागभोगाचलशृङ्गकल्पौविक्षिप्यबाहूगिरशृङ्गसारौ । निवृत्यवक्त्रंवडवामुखाभंनिशाचरोऽसौविकृतंजजृम्भे ।।6.60.56।।
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सः he, असौ devoid of beauty, निशाचरः Rakshasas, नागभोगाचलशृङ्गकृतौ like the coils of cobra, गिरिशृङ्गसारौ hard as mountain tops, बाहू limbs, विक्षिप्य thrown about, वडवामुखाभम् like submarine fire, वक्त्रम् mouth, विकृतम् unnatural, जजृम्भे yawned.
Kumbhakarna, devoid of any beauty threw out his limbs which were like the coils of cobra and as hard as mountain tops, his mouth was unnatural like a submarine fire as he yawned.