Valmiki Ramayana Bala Kanda Sarga 63 Shloka 5
Original Shlokaतां ददर्श महातेजा मेनकां कुशिकात्मज:। रूपेणाप्रतिमां तत्र विद्युतं जलदे यथा।।1.63.5।।
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महातेजा: highly lustrous, कुशिकात्मज: son of Kusika, Visvamitra, तत्र in that Pushkara, जलदे in the clouds, विद्युतं यथा like lightening, रूपेण in beauty, अप्रतिमाम् incomparable, ताम् मेनकाम् that Menaka, ददर्श beheld.
There the most brilliant son of Kusika Viswamitra saw Menaka whose beauty was incomparable. She looked like lightning in the clouds.