The most common and most likely answer to this crossword clue is the 9 letter word UNEATABLE
I've seen this crossword clue in The Times
U
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E
A
T
A
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More clues leading to the result UNEATABLE
- Impossible to improve without billions? That's not acceptable from restaurant
- Posh, well-groomed, talented, and disgusting when dining
- Not to be scoffed at, a French expert’s clothing
- Indigestible French article on a piece of furniture
- United, well-ordered and intelligent, though pursued unspeakably
- Foxes dapper sailor with rubber clothing
Buddy explains!
The straight part
We know that "not acceptable from restaurant" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case not acceptable from restaurant = uneatable.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 UNEATABLE mean?
UNEATABLE adjective- Not eatable; not fit for eating.