The most common and most likely answer to this crossword clue is the 9 letter word CARBONATE
C
A
R
B
O
N
A
T
E
More clues leading to the result CARBONATE
Buddy explains!
The straight part
We know that "salt" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case salt = carbonate.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 CARBONATE mean?
CARBONATE noun- Any salt or ester of carbonic acid.
- To charge (often a beverage) with carbon dioxide.