Passer un savon

Le mot du jour : “passer un savon”

“Passer un savon” (to brush with soap) is an expression that means to scold someone and not at all, as you would expect, to give a soap to someone.
So now that soap has become rare and precious, if a French person says “Je vais te passer un savon !”, don’t expect them to kindly share their soap with you but rather to give you an earful!

I am not sure where this expression comes from, but it always brings to my mind the image of a mum energetically washing her reluctant child 😀