i thought the phrase "getting a boner" referred to men getting their periods.
A childhood belief about rude bits

others believed things like this
- I used to believe that the phrase "Mamma Mia" referred to a girl named Mia.Anon
- i used to belive that a boner came from skeletons.— Bilunjan
- Until I was about 11 or 12 I thought that "prostitute" referred to a female criminal.Anon
- i thought that the phrase "jet lag" was actually "jet leg" until i was 17...— truffles
- I also used to think that Mommies didn't have periods. I thought it went away once you had a baby.— T
- When my mom was a child, she thought that while girls had periods, boys had hemorrhoids!Anon