Where does “Sostrate” come from?

Sostrate (French) comes from Middle French Sostrate, from Latin Sōstratus, from Ancient Greek Σώστρατος, from Ancient Greek σῶς, from Proto-Hellenic *twáwos.

Ancestry of “Sostrate”, step by step

Step	Language	Word	Meaning
1	Middle French	Sostrate	—
2	Latin	Sōstratus	—
3	Ancient Greek	Σώστρατος	—
4	Ancient Greek	σῶς	safe, sound, whole; safe, healthy, intact; safe...
5	Proto-Hellenic	*twáwos	—

Every word from Proto-Hellenic *twáwos →Every word from Ancient Greek σῶς →Every word from Ancient Greek Σώστρατος →