The most common and most likely answer to this crossword clue is the 8 letter word TANGOING
I've seen this crossword clue in The Sunday Telegraph
T
A
N
G
O
I
N
G
Buddy explains!

The straight part
We know that "Dancing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case dancing = tangoing.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 TANGOING mean?
TANGOING verb- To dance the tango.
- To mingle or interact (with each other).