The most common and most likely answer to this crossword clue is the 7 letter word OPPIDAN
I've seen this crossword clue in The Guardian
O
P
P
I
D
A
N
Buddy explains!

The straight part
We know that "Urban" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case urban = oppidan.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 OPPIDAN mean?
OPPIDAN noun- A town dweller.
- (also Oppidan) A class of student in traditional English public schools such as Eton; opposed to colleger or King's Scholar.
- Of or pertaining to a town or conurbation.