The most common and most likely answer to this crossword clue is the 8 letter word ANTIGONE
I've seen this crossword clue in The Guardian
A
N
T
I
G
O
N
E
More clues leading to the result ANTIGONE
- Tragic woman, person in opposition no more
- Rival dead in tragedy
- Political opponent disappeared in tragedy
- Opponent nowhere to be seen, a tragedy
- Oedipus’s daughter is against Greek individual
- With this, cantilever creates clever Greek drama
- Legendary female hybrid animal in a novel
- Her father and brother were as one in opposing Left
- Opposed to dead Greek tragedy
- Mythical daughter, opponent no longer with us
Buddy explains!
The straight part
We know that "Her father and brother were as one/Her father and brother were as one" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case her father and brother were as one/her father and brother were as one = antigone.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.