"Variant of Anastasia"
The name Nastasia is commonly a female name from the "Russian" origin.
Nastasia is a variant of Anastasia, the Greek name built on anastasis, meaning resurrection. Forms that drop the opening A, such as Russian Nastasya and Romanian Nastasia, are established in those languages rather than English inventions.
Anastasia means "Resurrection; springtime".
The pronunciation of Nastasia is nuh-STAY-zhuh.