Some opera I'd attended (4)
I believe the answer is:
aida
'some opera i'd attended' is the definition.
I can't tell whether this definition defines the answer.
'some opera i'd attended' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'AIDA' is hidden within 'opera id attended'.
Can you help me to learn more?
(Other definitions for aida that I've seen before include "Egyptian opera by 11 Down" , "work of grand proportions" , "she dies entombed" , "slave of Covent Garden" , "Verdi's opera set in ancient Egypt" .)