The most common and most likely answer to this crossword clue is the 9 letter word RETICENCE
I've seen this crossword clue in The Daily Telegraph
R
E
T
I
C
E
N
C
E
More clues leading to the result RETICENCE
- Reserve judgment in conversation about rite going ahead
- Not a Boris-like quality, taking refreshment in centre ground
- Reserve surprisingly nice tree, cheap initially
- Reserve of illicit drug found during recent reshuffle
- Taciturnity – reserve in centre for sculpture
- Reserve break in Crete supported by church
- There’s not much to say for having it
- Frost in centre affected reserve
- Erect nice building with modesty
- Expert dropping article on ground in Crete is low-key character
Buddy explains!

The straight part
We know that "Reserve" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case reserve = reticence.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 RETICENCE mean?
RETICENCE noun- An abrupt breaking-off in speech, often indicated in print using an ellipsis (…) or an em dash (—).
- Avoidance of saying or reluctance to say too much; discretion, tight-lippedness; an instance of acting in this manner.
- A silent and reserved nature.
- Followed by of: discretion or restraint in the use of something.
- Often followed by to: hesitancy or reluctance (to do something).
- To deliberately not listen or pay attention to; to disregard, to ignore.