As a deity name
Name 748 of the Gayatri Sahasranāma — Devi Bhagavata Purana, as taught by Sages
Name 413 of the Saraswati Sahasranāma — Skanda Purana, as taught by Lord Brahma / Sages
As a Hindi name
No reading on this path — this spelling has no entry in our Hindi sources, and no near neighbour is attested there either. We say so rather than invent one.
As a Sanskrit word
Meaning
[ bhāgīrathī smṛtā] 1 N. of the river Ganges; bhāgīrathīnirjharaśīkarāṇāṃ 2 N. of one of the three main branches of the Ganges.
Scripturally attestedWhy this matches what you typed
M1 · same meaning "bhāgīrathyai" is the dative of "bhāgīrathī" — the same word in a different grammatical case.
Dictionary citations
bhāgīrathī f. N. of the Ganges (or of one of the 3 main streams or branches of it, viz. the great western branch; cf. nava-dvīpa), MBh.; Kāv. &c.
bhāgīrathī f. of ˚ratha, in comp.
Caveats
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