As a deity name
Name 168 of the Lakshmi Sahasranāma — Skanda Purana / Sanat Kumara Samhita, as taught by Sages Sanatkumara and Devotees
As a Hindi name
सिनीवाली · noun · feminine
एक वैदिक देवी, मंत्रों में जिसका आह्वान सरस्वती आदि के साथ मिलता है · शुक्ल पक्ष की प्रातिपदा · अंगिरा की एक पुत्री का नाम — Śabdasāgara
सिनीवाली · sinīwālī · s.f.
The day of new moon; the day preceding that of new moon — Platts (1884), digital edition courtesy DSAL, University of Chicago, p. 690
As a Sanskrit word
Meaning
The day preceding that of new moon, or that day on which the moon rises with a scarcely visible crescent; yā pūrvāmāvāsyā; or kuhūḥ
Scripturally attested Verified derivationMultiple readings (2)Why this matches what you typed
The spelling you confirmed, सिनीवाली, is itself a dictionary headword — no grammatical transformation stands between what you typed and the meaning above.
Dictionary citations
sinīvālī f. (of doubtful derivation) N. of a goddess (in RV. described as broad-hipped, fair-armed, fair-fingered, presiding over fecundity and easy birth, and invoked with Sarasvatī, Rākā &c.; in AV. she is called the wife of Viṣṇu; in later Vedic texts she is the presiding deity of the first day of new moon, as Rākā of the actual day of full moon), the first day of new moon when it rises with a scarcely visible crescent, RV. &c. &c.
N. of a daughter of Aṅgiras, MBh.
of the wife of Dhātṛ and mother of Darśa, BhP.
of Durgā, L.
of a river, MārkP.
Alternative readings
More than one analysis survives full verification. That ambiguity is real, so we show every reading rather than pick one silently.
Caveats
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