The most common and most likely answer to this crossword clue is the 9 letter word GAUCHERIE
I've seen this crossword clue in The Times
G
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More clues leading to the result GAUCHERIE
- Lovelorn cowboy on lake shows tactless behaviour
- Bungling cowboy docked on lake
- Social awkwardness of Erica, huge, dishevelled
- It’s a faux pas to say die, darling
- Report of Blair encouraging his wife’s clumsiness
- France curtailed its girl’s clumsiness
- Grand Australian woman's clumsy
- Awkwardness of being a cow in India and dear in Paris
Buddy explains!

The straight part
We know that "tactless behaviour" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tactless behaviour = gaucherie.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 GAUCHERIE mean?
GAUCHERIE noun- A socially tactless or awkward act.
- Lack of tact; tactlessness; awkwardness.