The most common and most likely answer to this crossword clue is the 11 letter word QUARRELLING
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More clues leading to the result QUARRELLING
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The straight part
We know that "arguing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case arguing = quarrelling.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.
Crossword Answer definitions
QUARRELLING verb- To disagree.
- To contend, argue fiercely, squabble.
- To find fault; to cavil.
- To argue or squabble with.
- A heated argument.