The most common and most likely answer to this crossword clue is the 8 letter word PENSTOCK
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More clues leading to the result PENSTOCK
Buddy explains!
The straight part
We know that "Floodgate" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case floodgate = penstock.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 PENSTOCK mean?
PENSTOCK noun- A sluice or pipe which allows the controlled flow of water from behind a dam, typically routing it to a turbine of a power plant.
- The barrel of a wooden pump.