Can a planet be bigger than its star?

I get questions.

After posting an article here on the blog about an extremely low-density "superpuff" planet, I got an interesting question on Twitter:

["Have we ever found an exoplanet that was larger than its host star? Is that possible?"]

My first reaction was, "Yes! Kinda." And then I thought about it a little more, and realized the answer is actually, "Yes! But if you mean a star like the Sun, it's unlikely."

Explaining it would be a bit much for Twitter, but as it happens I have a bl...