I hate the word "swum." Maybe because I never have really been able to figure out its proper usage. But I hate how it sounds and I hate how it's spelled.
I don't like the word "drug" either. The spelling is ugly and when you say it, it's an ugly-sounding word. And it really bothers me when it's said related to something pharmaceutical and supposed to be helpful.
Other words that suck:
Frat (just bothers me to this day)
Barium (don't ask)
Slim
Potty
Pubic
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