The most common and most likely answer to this crossword clue is the 3 plus 3 letter word LET OUT
L
E
T
O
U
T
More clues leading to the result LET OUT
Buddy explains!

The straight part
We know that "Reveal" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case reveal = let out.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 LET OUT mean?
LET OUT noun- The act or an instance of releasing or letting out something.
- An opportunity to avoid or escape from a difficult or unpleasant situation.