bláx

blā́x agr. βλὰξ Trägheit, Schwerfälligkeit oder Schlaffheit;

Probably from Proto-Indo-European *ml̥h₂-k-s, from *ml̥h₂(e)k- (“weak”), which seems to be a zero-grade k-extension of *melh₂- (“to grind; crush”). Compare Sanskrit म्ला॒त (mlātá, “softened”, of leather), Proto-Celtic *mlātis (“tender; soft”), and perhaps Proto-Slavic *mьlčàti (“to be silent”); see also μᾰλᾰκός (mălăkós, “soft; gentle”).