Born in the Byzantine era (3)
I believe the answer is:
nee
'born' is the definition.
('nee' is 'born' in French)
'in the byzantine era' is the wordplay.
'in' indicates the answer is hidden within the clue.
'NEE' can be found hidden inside 'byzantine era'.
(Other definitions for nee that I've seen before include "Prefix denoting woman's name before marriage" , "Adjective meaning born, followed by maiden name" , "Name originally" , "It indicates a married woman's single name" , "Formerly named" .)