Ζωστηρίας

Ζωστήριος, of Ζωστήρ (epithet of Apollo and of Athena)

Morpho works with a static database. If you like, you can compare the output of Morpheus.

Parsed as:

proper-name adjective feminine accusative plural
✓ proper-name adjective feminine genitive singular of Ζωστήριος