The most common and most likely answer to this crossword clue is the 7 letter word YAKKING
I've seen this crossword clue in The Sunday Telegraph
Y
A
K
K
I
N
G
Buddy explains!

The straight part
We know that "Rabbiting" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rabbiting = yakking.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 YAKKING mean?
YAKKING verb- To talk, particularly informally but persistently; to chatter or prattle.
- To vomit, usually as a result of excessive alcohol consumption.