The most common and most likely answer to this crossword clue is the 8 letter word MIDNIGHT
I've seen this crossword clue in The Times
M
I
D
N
I
G
H
T
More clues leading to the result MIDNIGHT
- Headliners in Miles Davis evening covering start of iconic A Kind of Blue?
- Power to restrict horrible din late in the day
- Suggestion of G 12
- Power to restrict disorderly din at this late hour?
- When date changes I don’t oddly cut power
- 12 flipping thick, Lewis Hamilton now said
- G?
- G type of oil burnt by late work
- G12?
- Timing hand slipped losing an hour of darkness (8
Buddy explains!

The straight part
We know that "this late hour?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case this late hour? = midnight.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 MIDNIGHT mean?
MIDNIGHT noun- The middle of the night: the sixth temporal hour, equidistant between sunset and sunrise.
- 12 o'clock at night exactly.
- Utterly dark or black.