When I heard of the last name Armstrong, I thought it was the name given to people with strong arms and that last names involving body parts were common, for instance a woman with big eyes might be called "Molly Eyebig".
A childhood belief about names

others believed things like this
- I used to believe lepers came from Ireland. Like leprechauns, only with less body parts.Anon
- I used to think that bodily tissues were kleenex sheets that grew in certain parts of your body.Anon
- I used to believe that a funeral organist was the person who collected the body parts of the deadAnon
- I thought common as muck was a substance called commoners muck— oddsox
- When I was a kid I thought rape just meant someone tearing the clothes off of a woman's body.— Matt
- I was born brunette with brown eyes and dark hair, i thought people with blue eyes, had water in them.Anon