The most common and most likely answer to this crossword clue is the 9 letter word RIGHTEOUS
I've seen this crossword clue in The Times
R
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More clues leading to the result RIGHTEOUS
- Just sought ride having day off in resort
- Strangely, this rogue is not like a rogue
- Arranging is tougher for singing brothers
- This rogue reforms – becoming _________?
- Morally justifiable trick? Strange ethos – round the bend!
- Huge riots turned out to be justified
- This rogue turned out honest
- Godly sorts hug Tories
- Just ego’s hurt I fancy
- Just ego is hurt – badly
Buddy explains!

The straight part
We know that "not like a rogue" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case not like a rogue = righteous.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.
What does RIGHTEOUS mean?
RIGHTEOUS verb- To make righteous; specifically, to justify religiously, to absolve from sin.
- Free from sin or guilt.
- Moral and virtuous, to the point of sanctimonious.
- Justified morally.
- Awesome; great.