As a deity name
Name 357 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
great prosperity or power or perfection (in -prāpta N. of a prince of the Garuḍas, -mat possessing or conferring great pr˚ &c., a great sage, )
Scripturally attested Verified split — attested membersWhy this matches what you typed
M1 · same meaning "mahardhyai" is the dative of "maharddhi" — the same word in a different grammatical case.
Dictionary citations
maha—rddhi f. great prosperity or power or perfection (in -prāpta m. N. of a prince of the Garuḍas, Buddh.; -mat mfn. possessing or conferring great pr˚ &c., Cat.; m. a great sage, L.)
maha—rddhi mfn. very prosperous or powerful, R.; Kathās. (also ˚dhika, L., and ˚dhin, MBh.)
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