The most common and most likely answer to this crossword clue is the 9 letter word ALLOCATED
I've seen this crossword clue in Financial Times
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More clues leading to the result ALLOCATED
Buddy explains!
The straight part
We know that "Made an assignation" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case made an assignation = allocated.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 ALLOCATED mean?
ALLOCATED verb- To set aside for a purpose.
- To distribute according to a plan, generally followed by the adposition to.
- To reserve a portion of memory for use by a computer program.
- Having been granted an allocation; having received (something) as part of a plan or scheduled disbursement; having been assigned (something) that was set aside for a particular purpose.