Stolen from Laddy's thread clearly. This one however is about words you cannot say correctly despite knowing the correct way and spelling. I have 2...

1) Incendiary, my inability to pronounce this word is smurfing legendary on XBL Dan and Paul love to make me say the word or try to normally I just end up going "smurf you, it's a fire round/grenade"

2) Washing-up-liquid, more a 3 word name for something, I always say it wrong. How the hell do I say this wrong every time? I say Fairy-up-liquid. Yes Fairy. Have done this since I was a child.

So EoFF what words do you always say wrong despite knowing the correct way to do so?