Crossword Genius

Unstable (informal) (5)

Ross

I believe the answer is:

tippy

(Another definition for tippy that I've seen is " (Of boats) inclined to heel over easily".)

I've seen this clue in The Guardian.
Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.