The most common and most likely answer to this crossword clue is the 5 letter word NATTY
I've seen this crossword clue in The Daily Telegraph
N
A
T
T
Y
More clues leading to the result NATTY
- Smart part of America accommodating a Rechabite?
- Looking swanky a couple of times in US city
- _ora B_? Completing it would be smart
- Vote against adopting dry spruce
- Smart races, no outdated fences
- Dapper attorney in US city
- Concern at Tyson boxing clever
- Sharp old negative contains edges of tint
- Bad time for second trim
- Get spruce from leading North American tree traders? Yes!
Buddy explains!

The straight part
We know that "Sharp" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sharp = natty.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 NATTY mean?
NATTY adjective- Smart and fashionable.
- Knotty.
- Someone whose muscle gains are natural and not aided by the use of steroids.
- A national championship
- Natural, as opposed to steroid enhanced.
- National