The most common and most likely answer to this crossword clue is the 7 letter word POOREST
I've seen this crossword clue in The Daily Telegraph
P
O
O
R
E
S
T
More clues leading to the result POOREST
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The straight part
We know that "most short" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case most short = poorest.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 POOREST mean?
POOREST adjective- With no or few possessions or money, particularly in relation to contemporaries who do have them.
- Of low quality.
- Used to express pity.
- Deficient in a specified way.
- Inadequate, insufficient.
- Free from self-assertion; not proud or arrogant; meek.