The most common and most likely answer to this crossword clue is the 9 letter word INTEGRITY
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More clues leading to the result INTEGRITY
Buddy explains!

The straight part
We know that "Uprightness" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case uprightness = integrity.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 INTEGRITY mean?
INTEGRITY noun- Steadfast adherence to a strict moral or ethical code.
- The state of being wholesome; unimpaired
- The quality or condition of being complete; pure
- With regards to data encryption, ensuring that information is not altered by unauthorized persons in a way that is not detectable by authorized users.
- The ability of a system to provide timely warnings to users when they should not be used for navigation.