The most common and most likely answer to this crossword clue is the 9 letter word LASSITUDE
I've seen this crossword clue in Financial Times
L
A
S
S
I
T
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More clues leading to the result LASSITUDE
- Dog circles stallion dropping head in fatigue
- Freedom, with saints for the first time showing sluggishness
- Study discovered Dog Star orbits in inert state
- Languor shown as female setter ruined duet
- Lads use it, suffering lethargy
- Troubling us with details leads to lethargy
- Dog bitten by dog and bone gets fatigue
- Weariness in boss not having succeeded in film
- Weakness of female sex exposed when topless
- Exhaustion of girl with it due for treatment
Buddy explains!

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 LASSITUDE mean?
LASSITUDE noun- Lethargy or lack of energy; fatigue.
- Listlessness or languor.