The word shlag denounces the attitude of a worthless person who brags wrongly and who provokes disgust among those close to him.
Shlag has several meanings depending on the suburb of
France from which one comes.
But it appeared in the 90s, and in the 93 it was pejorative to see a
little insulting, while in the 92 it was more a person completely to the west, perched in the weed or other, who made "shlaggéitées" (unexpected and
strange stuff).