The most common and most likely answer to this crossword clue is the 9 letter word READINESS
I've seen this crossword clue in Financial Times
R
E
A
D
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S
More clues leading to the result READINESS
- Study by unit head is being prepared
- Study fashionable English ship's speed
- Set condition on when to partake of feasts?
- Facility to see above one’s head
- Being prepared to eat in a field, putting away starter and seconds
- Being prepared, add last of sauce to sardines in a stew
- Facility’s head tracks study on island
- Being prepared to study, I’ll get taken to head
- 15 Facility to see above one’s head
- Poorly aired on promontory but showing aptitude
Buddy explains!

The straight part
We know that "Set condition" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case set condition = readiness.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 READINESS mean?
READINESS noun- The state or degree of being ready; preparedness.
- Willingness.