an odd one from my own experience....although I am not sure its universal in America. When we moved out of our rental house over there, the landlady said that we had “stained” the carpet. We got a carpet cleaning service in and the carpet came up like new. Getting ready for a fight....we (nicely) let her know that we had the carpet cleaned and it hadn’t been stained, just dirtied from use.....got a really blank look “That’s what I meant” she said....explained that in the UK, if something is “stained” its more than just dirt and may not be removeable. Much relieved laughter all round.