The most common and most likely answer to this crossword clue is the 10 plus 6 letter word WASHING-UP LIQUID
I've seen this crossword clue in The Guardian
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More clues leading to the result WASHING-UP LIQUID
- Cleaner bizarrely dug his in-law quip
- With anguish tormented perfectionist initially left one pound for cleaner
- Cleaner whips a gun out, initially lifting £1
- Wife pounds clothing in huge pails, badly short of energy and detergent
- Distraught WI’s hang-up: £51 for cleaner?
- Fairy, perhaps, raised just over half a ton of cash to support tree strangled by branch
- Cleaner dog held up by his in-law, barking, given something to chew on
- Clue to make WAG punish cleaner
Buddy explains!

The straight part
We know that "Fairy, perhaps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fairy, perhaps = washing-up liquid.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.