As a deity name
Name 317 of the Gayatri Sahasranāma — Devi Bhagavata Purana, as taught by Sages
Name 633 of the Saraswati Sahasranāma — Skanda Purana, as taught by Lord Brahma / Sages
As a Hindi name
जाना
to go, leave, depart; to go to, extend; to be lost; an auxiliary verb
जाना · masculine
a Hindi word, a tadbhava: evolved from the Sanskrit through Prakrit ग॒त — per Wiktionary’s etymology record
“Etymology tree Proto-Indo-European *yeh₂- Proto-Indo-European *yéh₂ti Proto-Indo-Iranian *yáHti Proto-Indo-Aryan *yáHti Sanskrit याति॑ (yā́ti) Ashokan Prakrit 𑀬𑀸𑀢𑀺 (yāti) Prakrit जाइ (jāi) Hindi जाना Inherited from Prakrit जाइ (jāi), from Ashokan Prakrit 𑀬𑀸𑀢𑀺 (yāti), from Sanskri…” — per Wiktionary’s etymology record
a Hindi word; it is not Sanskrit
As a Sanskrit word
Meaning
‘daughter of Jahnu (q.v.)’, the Gaṅgā, (metrically ˚vi, ), &c.
Scripturally attestedWhy this matches what you typed
M1 · same meaning "jāhnavyai" is the dative of "jāhnavī" — the same word in a different grammatical case.
Dictionary citations
jāhnavī f. ‘daughter of Jahnu (q.v.)’, the Gaṅgā, MBh. iii, v, xiii (metrically ˚vi, 7680), Bhag.; Hariv. &c.
jāhnavī [jahroḥ apatyaṃ strī aṇ ṅīp] An epithet of the river Ganges.
Caveats
Sources contain errors and engines have limits; every claim above carries its citation so you can verify it. This is guidance about names and their sources — not religious or astrological consultation. How we work · Our sources