The most common and most likely answer to this crossword clue is the 6 letter word TORPOR
T
O
R
P
O
R
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The straight part
We know that "Sloth" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sloth = torpor.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 TORPOR mean?
TORPOR noun- A state of being inactive or stuporous.
- A state of apathy or lethargy.
- A state similar to hibernation characterised by energy-conserving, very deep sleep.