Concealed by opera star in The Times (4)
I believe the answer is:
eras
'times' is the definition.
(I've seen this before)
'concealed by opera star' is the wordplay.
'concealed' indicates a hidden word.
'ERAS' can be found hidden inside 'by opera star'.
'in the' is the link.
(Other definitions for eras that I've seen before include "Periods of time" , "Periods, ages" , "At least two times" , "Epochs" , "typeface" .)