The most common and most likely answer to this crossword clue is the 10 letter word MELANCHOLY
M
E
L
A
N
C
H
O
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Y
More clues leading to the result MELANCHOLY
- Spirit-filled host blessed the Blues
- Saddening to see Liberal shackled by selfish Conservative, highly revered
- Fruit and veg picked up, as down
- Sad Hindu festival initially not considered religious
- Spirit imbues leader of ceremonies with sacred 24 down
- Low fruit agricultural worker gathered in drum
- Fruit for dog, say, produces sadness
- Endlessly call holy men unbalanced — it leads to sadness
- Lonely champ lost, quietly left, sad
Buddy explains!

The straight part
We know that "sadness" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sadness = melancholy.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 MELANCHOLY mean?
MELANCHOLY noun- Black bile, formerly thought to be one of the four "cardinal humours" of animal bodies.
- Great sadness or depression, especially of a thoughtful or introspective nature.
- Affected with great sadness or depression.