Titaness back on the radio? (4)
I believe the answer is:
rhea
'titaness' is the definition.
(Rhea is an example)
'back on the radio?' is the wordplay.
'back' becomes 'rear' (something's rear is its back).
'on the radio?' indicates a 'sounds like' (homophone) clue (I've seen 'on the radio' mean this).
'rear' sounds like 'RHEA'.
(Other definitions for rhea that I've seen before include "South American flightless bird - mother of Zeus" , "Moon" , "Flightless bird from South America" , "Ostrich-like bird - satellite of Saturn" , "New World ostrich" .)