The most common and most likely answer to this crossword clue is the 4 plus 2 letter word WIND UP
I've seen this crossword clue in The Daily Telegraph
W
I
N
D
U
P
More clues leading to the result WIND UP
- Success with Irish party to end
- Joke the nervous get
- What fearful people have to finish?
- Patting baby’s back, parent may get this close?
- Worried person is said to have this finish
- Bring an end to anger through teasing
- Empty words in court irritate
- Agitate snake with increased vigour
- Close to anger
- Close company
Buddy explains!

The straight part
We know that "finish" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case finish = wind up.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 WIND UP mean?
WIND UP noun- The end or conclusion of something.
- A punch line of a joke or comedy routine.
- A humorous attempt to fool somebody, a practical joke in which the victim is encouraged to believe something untrue.
- The phase of making a pitch where the pitcher moves his or her arm backwards before throwing the ball.
- A circular hand gesture, supposed to represent the winding on of film, used to signal to a performer to finish quickly.
- (of a machine) Needing to be wound up in order to function.