I used to believe that "vagina" (or "magina" as I heard it) was a fancy word for crotch. And my friend said this about having sex: "You put your magina into the other person's magina..."
A childhood belief about rude bits

others believed things like this
- In first grade, I thought that if I've never heard of a word before, then it wasn't a word.— Destiny
- I used to think that fart was a bad word and then i heard my mom say it once and I was so shocked.— Tara
- i used to think that oral sex was just a fancy term for kissingAnon
- When I was young, I heard the word 'minion' for the first time and thought it was a miniature onion.— Karin
- when i first heard the name "blow job",i thought the meaning of that word was blowing a snot out of your nose.— myuka
- For years I heard the word "pedophile" and thought it meant a pedicurist's tool.— Lauren