The most common and most likely answer to this crossword clue is the 4 letter word RACY
R
A
C
Y
More clues leading to the result RACY
- Clubs wearing light blue
- Blue vehicle, turning over, last in rally
- Naughty drivers close to boundary
- Lively motor returned by end of January
- A bit dirty, caught in some light
- Blue fish rounding cape
- Naughty or extremely angelic, kept in line
- Tory wearing light blue
- Pungent fish stuffed with bit of coriander
- Woman with no time to be sexy
Buddy explains!

The straight part
We know that "blue" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case blue = racy.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 RACY mean?
RACY adjective- Mildly risqué.
- Having a strong flavor indicating origin; of distinct characteristic taste; tasting of the soil.
- (by extension) Exciting to the mind by a strong or distinctive character of thought or language; peculiar and piquant; fresh and lively.
- Involving a data race or a race condition.