The most common and most likely answer to this crossword clue is the 7 letter word AQUIFER
I've seen this crossword clue in Independent
A
Q
U
I
F
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R
More clues leading to the result AQUIFER
- What holds water in a raised lock, not following English river
- Trembling female replacing Victor's source of water
- Raging fire following a question getting source of water
- Answer question on fire raging in water-bearing rock!
- A question to deduce — without corroboration, ultimately, will it hold water?
- A question, I fear, that excludes a water-source
- Water supply American provided in Queens?
- A judge brought up previously in Bordeaux who is underground drink supplier
Buddy explains!
The straight part
We know that "Water supply" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case water supply = aquifer.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 AQUIFER mean?
AQUIFER noun- An underground layer of water-bearing porous stone, earth, or gravel