Orestes' sister set apart right article (7)

I believe the answer is:

electra

I'm a little stuck... Click here to teach me more about this clue!

'orestes' sister' is the definition.
(I've seen this in another clue)

'set apart right article' is the wordplay.
'set apart' becomes 'elect' (I can't explain this - if you can you should believe this answer much more).
'right' becomes 'r' (common abbreviation).
'article' becomes 'a' (the indefinite article in English).
'elect'+'r'+'a'='ELECTRA'

Can you help me to learn more?

(Other definitions for electra that I've seen before include "type of complex" , "Tragic daughter of Agamemnon" , "titled lady" , "Sister of Orestes" , "Complex girl" .)

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.