What does “vaurien” mean in French?

Un vaurien is a good-for-nothing, a rascal. Read it slowly and it explains itself: vau-rien is vaut rien, “is worth nothing,” from the verb valoir. It sounds a little old-fashioned, more like a grandparent scolding a troublemaker than a modern insult, which makes it handy for teasing. The feminine vaurienne exists but is rare.

French has other compressed sentence-words like this, such as un je-ne-sais-quoi (“a certain something”) and un m’as-tu-vu (“a show-off,” from “did you see me?”). In this dubbed scene a bully gets warned off with laisse Peter tranquille (“leave Peter alone”) and a final ce n’est pas ton jour de chance, vaurien, “it’s not your lucky day, you little rascal.”