The most common and most likely answer to this crossword clue is the 7 letter word MID-AIR
I've seen this crossword clue in The Guardian
M
I
D
-
A
I
R
Buddy explains!

The straight part
We know that "above ground level" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case above ground level = mid-air.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 MID-AIR mean?
MID-AIR noun- The middle of the air, as while in flight.