The most common and most likely answer to this crossword clue is the 8 letter word MISTIMED
I've seen this crossword clue in The Sunday Telegraph
M
I
S
T
I
M
E
D
More clues leading to the result MISTIMED
Buddy explains!
The straight part
We know that "done at the wrong moment" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case done at the wrong moment = mistimed.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 MISTIMED mean?
MISTIMED verb- To do at the wrong time; especially to misjudge the timing of coordinated events.
- Done at the wrong time.