Threicius
Could not find Threiciam in Logeion dictionaries.
Threiciam Proper-name adjective: feminine accusative singular of Threicius
Thrēĭcĭus, a, um, v. Thracia, D.
Thrēicius, -issa, s. Thrāces.
Thrēĭcĭus, (11) a, um (Θρηΐκιος), de Thrace : Virg. En. 6, 645 ; Hor. O. 1, 24, 13 ; Ov. M. 11, 2.