Valmiki Ramayana Aranya Kanda Sarga 56 Shloka 2
Original Shlokaराजा दशरथो नाम धर्मसेतुरिवाचलः। सत्यसन्धः परिज्ञातो यस्य पुत्रस्सराघवः।।3.56.2।।
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दशरथो नाम named Dasaratha, राजा king, अचलः steadfast, धर्मसेतुरिव as an embankment (protector) of righteousness, सत्यसन्धः true to his promise, परिज्ञातः renowned, सः राघवः that Rama, यस्य whose, पुत्रः son.
Rama is a son of the renowned king Dasaratha, who was a firm ambankment (protector) of righteousness and was true to his promise.