In ancient Indian historical geography the name ‘Ratnakara’ denoted

In classical Indian geographical terminology ‘Ratnakara’ commonly denotes the great sea or ocean surrounding the subcontinent rather than a specific coastal bay or river-confluence. Ancient and classical geographical treatments distinguish the two principal seas flanking peninsular India (the Arabian Sea and the Bay of Bengal) while treating the broader maritime domain as the Indian Ocean or great oceanic expanse; scholarly treatments of ancient Indian geography therefore equate terms meaning “sea/ocean” with the larger Indian Ocean concept rather than a single bay or inland confluence [3]. Consequently, the best fit among the options is the Indian Ocean (the great oceanic body).

Sources

1. [1] CONTEMPORARY INDIA-I ,Geography, Class IX . NCERT(Revised ed 2025) > Chapter 2: Physical Features of India > The Coastal Plains > p. 13
2. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 29: El Nino, La Nina & El Nino Modoki > Impact of IOD On Cyclogenesis In Northern Indian Ocean > p. 416
3. [3] https://ia804607.us.archive.org/29/items/in.ernet.dli.2015.462637/2015.462637.Studies-In_text.pdf