The most common and most likely answer to this crossword clue is the 10 letter word INDISPOSED
I've seen this crossword clue in The Daily Telegraph
I
N
D
I
S
P
O
S
E
D
More clues leading to the result INDISPOSED
- Trendy daughter is presented poorly
- Sick sort of film director taking concessions back
- I’d spend, so I could become unwell
- Home Guard’s rear is positioned poorly
- Twisted spine is odd being laid up
- Unwilling, being sick
- At home, sat mock, previously unwilling
- At home daughter is model daughter too unwell to help?
- Unwilling to be sick
- Being unwell, I had to conceal terrible dopiness
Buddy explains!

The straight part
We know that "Unwilling/sick" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unwilling/sick = indisposed.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 INDISPOSED mean?
INDISPOSED adjective- Mildly ill.
- Not disposed, predisposed, or inclined; unwilling.
- Not yet ready (especially with regard to receiving a visitor) because not yet arranged into a state of readiness (i.e., not disposed); (especially, more specifically):