Lots of questions about verlan in the last few hours. It is not my favorite way of expression but it can be surprising at times. The reflex is difficult to acquire I think. The topic didn't make it to the discussion page unfortunately so here is part of it.

Perhaps someone can add to it.

Le verlan= l' envers// French backwards

quelques exemples:

pourri => ripou

when the last letter is a silent "e", insist on it when pronuoncing before turning the syllables aroud:

femme=> femmeu=> meuff=> meuf

fête=> fêteu =>teuf

Sometimes it is not clear...

work=> taf

Voilà, I hope it helps. It is not easy!! There are several sources of info about verlan online.

Bonne soirée à toutes et à tous.

Confidence I do not have with Verlan. I am glad you do! and yes it seems pretty hopeless in written form.

It's quite possible; It sounds like you are quite familiar with it.

I am finding here and there that it may go much further back than the 19th C.

My mother-in-law, who grew up next to the slaughterhouses in La Villette in the 20th in Paris, swears that verlan was created by the butchers and other meat workers during the 19th C.

The first time I met her she used quite a bit and I couldn't understand anything she said. My husband uses it frequently being the good Parisian boy that he is.

I've always liked " Laisse béton". That's about all that is in verlan in the song, the rest is colourful argot.
Is there more verlan in Dutronc' s song?

There are many unexpected and interesting examples of this type of modifications in the French language of past centuries.

the singer renaud used the verlan in his songs like “laisse bétom” for laisse tomber … ou Jacques dutronc avec "J’avais la vellecère qui zéfait des gueuvas "