When my eldest daughter started at her sixth form college, after years of private school, she got labelled “posh”.
For one thing she said “prep” instead of “homework”.
Posh kids say “mummy I haven’t got any prep tonight.” Apparently.
I bought her one of those old school badges you can get in novelty shops that said “posh” on it. She wore it on the lapel of her jacket with pride. It became a bit of a joke in our family.
If you met us you would know instantly that we are anything but posh.