The most common and most likely answer to this crossword clue is the 5 plus 3 letter word NIGHT OWL
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More clues leading to the result NIGHT OWL
- Late worker close to empty well
- Late sleeper puts own light off
- Upset with long day-time sleeper
- One who puts off retirement due to wife leaving primarily
- Bird is close and drier having abandoned side of lake
- Late sleeper is close to Welsh lake
- One stays up to work with long novel
- One working late has arranged own light
- I work late with long breaks
- One unused to early retirement?
Buddy explains!

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 NIGHT OWL mean?
NIGHT OWL noun- An owl (order Strigiformes) that is nocturnal.
- One who goes to bed late, or stays up late at night or in the early hours of the morning.
- A musical instrument which imitates an owl's hoot, consisting of a receptacle partly filled with water and a mouthpiece that is blown into.