What does “purée” mean when French people say it as an exclamation?

Purée is mashed potato, but shouted on its own, purée ! is a softened swear word. It stands in for putain, the most common French curse, and borrows its first sound, the way English says “shoot” or “fudge.” It expresses frustration or surprise without the vulgarity, so it’s fine in front of kids or parents. Purée, il fait trop chaud is “gosh, it’s so hot.”

It has siblings that do the same job: punaise ! (literally “bedbug” or “drawing pin”), mince ! and zut !. In this sketch a teenager can’t sleep the night before school starts and moans purée, il fait trop chaud là, then ça me gonfle (“this is getting on my nerves”), before a friend calls with bad news about class lists.