Usually occurs when a person has had a bad diet of wine and pomme-frites.
Je ne veux pas avoir un mauvais calvert - I do not want a bad shit
n. a person who lies, deceives or embellishes to make themselver look tougher, more experienced or smarter than they are.
"Don't try and pull a Calvert on me, we all know you don't own a Porsche"
Person 2: Calvert.
Person 1: Oh, I wonder if that name comes from the latin root "Calvus?" He seems like he has a full head of hair though, so it must be a nickname passed down from a bald ancestor. Other than that, I can infer nothing about his personality, economic status, or any other personality traits.
Person 3: Calvert is a name which spans all races!