poudre de perlimpinpin

Attested since the 17th century, originally as poudre de prelimpinpin. Compare Portuguese pó de perlimpimpim.

• IPA^(key): /pu.dʁə d(ə) pɛʁ.lɛ̃.pɛ̃.pɛ̃/

poudre de perlimpinpin f (usually uncountable, plural poudres de perlimpinpin)

1. a powder, purported to have magic powers, formerly sold by charlatans
2. (by extension, idiomatic) snake oil (a fraudulent cure-all or remedy)
   • 2017, Emmanuel Macron, 2017, le débat, TF1/France 2:

     Donc ce que vous proposez, comme d’habitude, c’est de la poudre de perlimpinpin.

     So what you have to offer, as usual, is nothing but snake oil.

• “perlimpinpin”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012.