The most common and most likely answer to this crossword clue is the 5 plus 3 letter word BREAK OFF
I've seen this crossword clue in The Daily Telegraph
B
R
E
A
K
O
F
F
Buddy explains!
The straight part
We know that "Abruptly end" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case abruptly end = break off.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 BREAK OFF mean?
BREAK OFF noun- That which breaks off, or is broken off
- A break, discontinuance, or interruption
- The first shot in a game of snooker or other cue-game
- To play the first shot in a game of snooker