Definitely the "C" word! The "F" word that is british for cigarette too. The word panties - if you are talking about adult undergarments they are underwear, thongs, boxers, etc.
Accents are fun and add flavor ..... adding letters and misspeaking drives me nuts and makes you sound like an uneducated moron! If you are over the age of 7 and don't have a speech impediment, enunciate and use the correct word! It's not cute after that age!
Announcers who mispronounce basic things drive me nuts too - they're on national television, yet don't know how to say the names of states correctly? WTF!