The most common and most likely answer to this crossword clue is the 10 letter word WATERWORKS
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The straight part
We know that "much weeping" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case much weeping = waterworks.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 WATERWORKS mean?
WATERWORKS noun- The water supply system of a town etc., including reservoirs, pumps and pipes.
- Any single facility, such as a filtration plant, within such a system.
- Tears; crying.
- The genitourinary system.