The most common and most likely answer to this crossword clue is the 5 letter word RUNNY
R
U
N
N
Y
More clues leading to the result RUNNY
- Not set to race where famous marathon takes place
- What one US mayor will do in a fluid way
- Manage money regularly after losing capital like water
- Far from stiff from marathon, perhaps, west of New York
- What Giuliani used to do is not solid
- Ladder to point unknown is not all solid
- Flowing river with no force creating diversion
- Not set to take charge of US city
- Before new year, manage to be thin
- Fluid, like a successful innings?
Buddy explains!

The straight part
We know that "not all solid" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case not all solid = runny.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 RUNNY mean?
RUNNY adjective- Fluid; capable of flowing.
- Liable to run or drip.