One of mine that has stood the test of time is "fourble" -- as in double, treble, fourble. It's much faster to say than quadruple. Saves energy. Unless, of course, I'm talking to a grammar Nazi who wants to argue about it.
I invented a few Japanese words when I was working for them, too. They're very polite people and "Chotomate kudasai" means "Just a moment, please" but my choto-bloody-mate was faster. It sent them away laughing, but it did send them away.
I've got two for you. One of my closest friends is African American and I call him my briend. He calls me his criend.
Black friend
Caucasian friend.
Well sometimes I've been known to make up my own words. Most of the time they are nicknames for people or animals in my life.
Boo-pah is my son's nickname from his childhood. Haven't called him that in years. His full nickname was Boo-pah the Booper Scooper. It was his secret safety word also.
My daughter has had many but she was called Her-vee. She had cheeks as big as a Humvee. So she wasn't a Him-vee she's a Her-vee.
I call my dog a "Duppy", because she is a dingy puppy.
I know.. I know...we have problems... Lol
Crappenheimer ! Nickname for my Hound dog ! You get the idea ! LOL. His favorite thing to do I think !