The most common and most likely answer to this crossword clue is the 6 letter word ZIGZAG
Z
I
G
Z
A
G
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The straight part
We know that "Wavy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wavy = zigzag.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 ZIGZAG mean?
ZIGZAG noun- A line or path that proceeds by sharp turns in alternating directions
- One of such sharp turns
- To move or to twist in a zigzag manner.
- Moving in, or having a zigzag.
- In a zigzag manner or pattern