The most common and most likely answer to this crossword clue is the 7 letter word DANCING
D
A
N
C
I
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G
Buddy explains!

The straight part
We know that "caper" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case caper = dancing.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 DANCING mean?
DANCING verb- To move with rhythmic steps or movements, especially in time to music.
- To leap or move lightly and rapidly.
- To perform the steps to.
- To cause to dance, or move nimbly or merrily about.
- To make love or have sex.
- The activity of taking part in a dance.
- A dance club in France.