The most common and most likely answer to this crossword clue is the 9 letter word ADULTERER
I've seen this crossword clue in Financial Times
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More clues leading to the result ADULTERER
- One scoring away from home?
- Breaking rule with date, right? I am
- Person who’s 16 is more grown up about coming back
- Letter oddly penned by a German artist — one’s not true
- Married man who later rued arrangement
- Rule trade out with one known to cheat
- Man with another man’s woman is kinky later
- Luther oddly stops a German artist, one who cheats
- Husband affected by wanderlust you could say
- Who later rued straying?
Buddy explains!
The straight part
We know that "one known to cheat" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one known to cheat = adulterer.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 ADULTERER mean?
ADULTERER noun- One who commits adultery: a spouse who has sex with a non-spouse
- A male adulterer specifically, opposite adulteress referring to female ones.