What do they mean by Gypsy's ribbon?

Oh, dude, the term "Gypsy's ribbon" is just a slang way of referring to a rainbow. You know, like how a ribbon has all those different colors? It's the same idea with a rainbow - a colorful arc in the sky after rain. So, if someone mentions a Gypsy's ribbon, they're just talking about that beautiful, multicolored natural phenomenon.