The most common and most likely answer to this crossword clue is the 7 letter word MOPPING
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Buddy explains!
The straight part
We know that "Cleaning" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cleaning = mopping.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 MOPPING mean?
MOPPING verb- To rub, scrub, clean or wipe with a mop, or as if with a mop.
- To make a wry expression with the mouth.
- The process of cleaning with a mop.
- An application of molten asphalt to a roof etc.