The most common and most likely answer to this crossword clue is the 8 letter word NO-SHOWS
I've seen this crossword clue in The Guardian
N
O
-
S
H
O
W
S
More clues leading to the result NO-SHOWS
Buddy explains!
The straight part
We know that "They are missing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case they are missing = no-shows.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 NO-SHOWS mean?
NO-SHOWS noun- An absence; failure to show up or to make a scheduled appearance, especially at a hotel or a place of employment.
- A person or group that does not show up.
- To fail to show up for something.