The most common and most likely answer to this crossword clue is the 7 letter word FLOUNCE
I've seen this crossword clue in Financial Times
F
L
O
U
N
C
E
More clues leading to the result FLOUNCE
- Go with disdain, having no time for feral cat
- Petulant movement suggesting old imperial unit?
- Flop like a fluid cat?
- Exaggerated walk after 1/20th of a pint?
- Decorative piece on garment creating storm
- Dejected, kicking out at cat to show annoyance
- Stamp showing 1/20 pint?
- Ruffle flight lieutenant’s cat
- Walk indignantly away from fringe
- Stalk fluid snow leopard
Buddy explains!

The straight part
We know that "Flop" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case flop = flounce.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 FLOUNCE mean?
FLOUNCE noun- A strip of decorative material, usually pleated, attached along one edge; a ruffle.W
- The act of flouncing.
- To move in an exaggerated, bouncy manner.
- To flounder; to make spastic motions.
- To decorate with a flounce.
- To depart in a haughty, dramatic way that draws attention to oneself.