From Chemgal:

She notes, “I know phase changes, and expect someone else will immediately understand the bouba and kiki part, but I do not.”

Not sure “immediately” is the operative term, but it did sound vaguely familiar; Google finds https://en.wikipedia.org/wiki/Bouba/kiki_effect, now alles klar. Even more interesting is searching “kiki bouba english”, which reveals that it’s not just an English phenomenon, although it does vary somewhat.

Oh, and hovertext is:

Even when you try to make nice, smooth ice cubes in a freezer, sometimes one of them will shoot out a random ice spike, which physicists ascribe to kiki conservation.