Is there a certain word that...?

no matter what you do...you don't pronounce it right the first time you say it?

OR a word that for some reason you always say a different word other than what you meant?

EXAMPLE: I always say "trenviliquist" instead of Ventriloquist!

Also, whenever I go to say Pelican, I always say Penguin and vice verse! I even do it when I'm aware that I might and try hard not to!

I always laugh at myself, but I'm seriously trying not to do it. :)