The name Theodosia is a girl's name of Greek, Russian origin meaning "giving to God". Theodosia and is often added to lists like Unique Baby Names: Unusual and Rare and discussed in our forums with posts like "Baby a Day".
From the experts:
This feminine form of Theodosius has long been buried deep in the attic, but might be a good discovery for the parent who wants to move beyond Theodora. Vice President Aaron Burr named a daughter Theodosia ("Dear Theodosia" is a song in the smash musical Hamilton), and it was the birth name of silent screen vamp Theda Bara. Theodosia actually appeared on the US popularity lists in the 1880s and 90s.