The most common and most likely answer to this crossword clue is the 7 letter word TEETERS
T
E
E
T
E
R
S
Buddy explains!

The straight part
We know that "is wavering" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case is wavering = teeters.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 TEETERS mean?
TEETERS verb- To tilt back and forth on an edge.
- To be indecisive.
- To be close to becoming a typically negative situation.