As a psychologist, I’d long known that people can easily determine which of the below two shapes is named Bouba and which is named Kiki.
Kiki sounds hard, so people associate it with the sharp shape, while Bouba sounds round and goes with the round shape.
I learned more recently from reading Slate’s excerpt from a book about the language of food that Kiki and Bouba are also attributable to different types of chocolate. Specifically, milk chocolate, with its smooth mouthfeel, is associated with Bouba. Dark chocolate, with its sharper flavors, is associated with Kiki.
Pretty cool, huh? Also this means you should think twice about what you name your chocolate company, as people may form expectations about what your product will taste like based on how sharp or round its name is.