The most common and most likely answer to this crossword clue is the 9 letter word NICKNAMES
I've seen this crossword clue in Financial Times
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More clues leading to the result NICKNAMES
- Informally, handles collars worn by celebrity
- Swinging men, as shown by cooler sobriquets
- Steal Handel’s so-called familiar titles
- Nicky and Nico – but not Nicholas?
- Old Scratch and Lucifer, say — or Parkhurst and Newgate?
- . Dubs celebrity arrests to be 'superficial'
- Familiar addresses to steal by illegal means
- Unofficial titles such as clink and choky
- Alternative appellations: Dickens, Lucifer etc?
Buddy explains!
The straight part
We know that "Unofficial titles" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unofficial titles = nicknames.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 NICKNAMES mean?
NICKNAMES noun- A familiar, invented given name for a person or thing used instead of the actual name of the person or thing.
- A kind of byname that describes a person by a characteristic of that person.