The most common and most likely answer to this crossword clue is the 9 letter word DESTITUTE
I've seen this crossword clue in Financial Times
D
E
S
T
I
T
U
T
E
More clues leading to the result DESTITUTE
Buddy explains!

The straight part
We know that "Poor" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case poor = destitute.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 DESTITUTE mean?
DESTITUTE adjective- (followed by the preposition "of") Lacking something; devoid
- Lacking money; poor, impoverished
- To impoverish; to strip of wealth, resources, etc.