The most common and most likely answer to this crossword clue is the 12 letter word METROPOLITAN
I've seen this crossword clue in Financial Times
M
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T
R
O
P
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L
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A
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More clues leading to the result METROPOLITAN
Buddy explains!
The straight part
We know that "characteristic of London perhaps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case characteristic of london perhaps = metropolitan.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 METROPOLITAN mean?
METROPOLITAN noun- A bishop empowered to oversee other bishops; an archbishop.
- The inhabitant of a metropolis.
- Pertaining to the see or province of a metropolitan.
- Of, or pertaining to, a metropolis or other large urban settlement.