The most common and most likely answer to this crossword clue is the 7 letter word HAPLESS
I've seen this crossword clue in The Times
H
A
P
L
E
S
S
More clues leading to the result HAPLESS
- Poor leaders in his August papers – like every silly season?
- Unfortunate fellow, beheaded, gets smaller
- Unfortunate lapses following treatment introduced by hospital
- Unlucky, like chap that’s caught short
- Unlucky, pal, she’s dodgy
- Unlucky chap like this is a hundred?
- Unfortunate way of spelling “speshal”
- Doctor helps to restrain a second unfortunate
- Unfortunate student in poor shape finishes at last
- Unfortunate — splashed endlessly around
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 = hapless.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 HAPLESS mean?
HAPLESS adjective- Very unlucky; ill-fated.
- Devoid of talent or skill.