Dwitiya

Dwitiya also referred to as Beej and Dooj is the Sanskrit word for "second", and is the second day in the lunar fortnight (Paksha) of the Hindu calendar. Each month has two Dwitiya days, being the second day of the "bright" (Shukla) and of the "dark" (Krishna) fortnights respectively. Thus Dwitiya occurs on the second and the seventeenth day of each month.

...
Wikipedia