This is an interesting topic that came to mind and I wanted to see other people's opinions, so here are my most hated words:
Gamer - Why?: I don't know why but it just sounds extremely cringy to me. It makes it worse when I see little kids wearing Minecraft shirts saying "Hardcore Gamer"
Succulent - Why?: Same thing as moist, but 10x worse.
Meal - Why?: I don't really have an explanation for this one, but the way certain people say it is unnerving. The letter M and how it just doesn't fit with the eal part is the thing that sets off my hatred for this word. It just doesn't sound right.