The most common and most likely answer to this crossword clue is the 8 letter word DRUNKARD
I've seen this crossword clue in The Daily Telegraph
D
R
U
N
K
A
R
D
More clues leading to the result DRUNKARD
- An over-indulgent draughtsman?
- Inebriate daughter, after dash in dark, collapsed
- Toper or libertine mostly in retreat, held by doctor and in Germany
- Doctor treated Kurd, an alkie
- Boozer finally tucking into dark, dark rum?
- . Soak in river during dip, not easy when head is submerged
- Doctors from North and South wrapped penniless Indian fan in sponge
- Wino died after trip in dark, delirious
Buddy explains!

The straight part
We know that "Toper" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case toper = drunkard.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 DRUNKARD mean?
DRUNKARD noun- (somewhat derogatory) A person who is habitually drunk.