Ignorant
Growing up, I used to think that ignorant meant what rude does. That was how my mom used it. If we were being rude, misbehaving, etc. she’d tell us to stop being ignorant. It wasn’t until high school or college that I found out what it really meant.
I used to chalk this up to my mom’s atypical Greek/African upbringing. It’s not that hard to see how rude & ignorant could become mixed up, as I’m sure someone being rude often is the result of ignorance. However, watching a recent episode of My Fair Brady, Christopher Knight (a.k.a. Peter Brady) says something rude to Adrianne’s mom while visiting Joliet, to which the mom replies “You know, that’s very ignorant.”
I think I just unearthed a piece of etymology of my mom’s vocabulary.
