Maybe ring with a time to come over (5)
I believe the answer is:
arena
'maybe ring' is the definition.
(eg a boxing ring)
'with a time to come over' is the wordplay.
'with' says to put letters next to each other.
'a' becomes 'an'.
'time' becomes 'era' (an era is a period of time).
'to come over' says the letters should be written in reverse.
'an' next to 'era' is 'anera'.
'anera' written backwards gives 'ARENA'.
(Other definitions for arena that I've seen before include "Earls Court?" , "Scene of gladiatorial contest, perhaps" , "The place of action" , "Field of combat" , "Sphere of intense activity" .)