The most common and most likely answer to this crossword clue is the 7 letter word TUESDAY
I've seen this crossword clue in The Guardian
T
U
E
S
D
A
Y
More clues leading to the result TUESDAY
- A study developed around English calendar item
- Filled with energy, reorganised a study period
- Irregularly, stayed outside university for part of the week
- Sea duty arranged — twenty-four hours
- Time to tidy up a dusty office finally
- Sea duty organised for 24-hour period
- After travelling, you finally stayed for 24 hours
- Weld actress to graceful child
- Period used to redesign Scottish river housing
- Weekly occurrence of tourers’ and diary’s odd things
Buddy explains!
The straight part
We know that "24 hours" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case 24 hours = tuesday.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.