The most common and most likely answer to this crossword clue is the 2 plus 3 plus 5 letter word AT THE READY
I've seen this crossword clue in Financial Times
A
T
T
H
E
R
E
A
D
Y
More clues leading to the result AT THE READY
- Always keeping dry, he looked over, poised for action
- After a short time that lot will embrace study — keen to get going?
- Set apart, gutted, they bypass study
- Prepared tea tray he’d ordered
- Prepared in a little yard not at this location
- A small amount around that place’s finally, finally
- For cooking, heated tray available now
- Prepared to be plundering supply of cash?
- He’d a treaty drawn up, poised for action
- Liable to get fired soon, interfering with cash?
Buddy explains!

The straight part
We know that "Prepared" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case prepared = at the ready.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.