The most common and most likely answer to this crossword clue is the 6 letter word PURGED
I've seen this crossword clue in The Guardian
P
U
R
G
E
D
Buddy explains!

The straight part
We know that "cleaned" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cleaned = purged.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 PURGED mean?
PURGED verb- To clean thoroughly; to cleanse; to rid of impurities.
- To free from sin, guilt, or the burden or responsibility of misdeeds
- To remove by cleansing; to wash away.
- To void or evacuate (the bowels or the stomach); to defecate or vomit.
- To cause someone to purge, operate on (somebody) as or with a cathartic or emetic, or in a similar manner.
- To clear of a charge, suspicion, or imputation
- To clarify; to clear the dregs from (liquor).
- To become pure, as by clarification.
- To have or produce frequent evacuations from the intestines, as by means of a cathartic.
- To trim, dress or prune.