The word moist is pretty unpopular: Almost one in five people say they're averse to it.  A Moist Crevice for Word Aversion: In Semantics Not Sounds 
Thibodeau PH (2016) A Moist Crevice for Word Aversion: In Semantics Not Sounds. PLOS ONE 11(4): e0153686. https://doi.org/10.1371/journal.pone.0153686
But why? We don't mind the words foist or hoist, which means it's probably not the sound of the word. Most of us are fine describing a slice of cake as moist, so it likely has something to do with the other ways we use the word—and the things we associate it with (for example, gross bodily functions). Or, as this video from Mashable suggests, we might just hate moist because everyone hates moist. We'll let them explain.

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