Question: what are the worst words you can say?
Answer: Colonel. “Colonel” is just an unwieldy disaster of phonetics and it spits in the face of the English language. ... 
Rural. There is no graceful way to say rural. ... 
Fester. The fricative “f” sound meets the perfectly innocuous “-ester” to create something that's just abominable. ... 
Puce. ... 
Squelch. ... 
February. ... 
Pustule. ... 
Bosom.