The most common and most likely answer to this crossword clue is the 9 letter word SACCHARIN
I've seen this crossword clue in The Guardian
S
A
C
C
H
A
R
I
N
More clues leading to the result SACCHARIN
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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 SACCHARIN mean?
SACCHARIN noun- A white, crystalline powder, C7H5NO3S, used as an artificial sweetener in food products