I hasten to add the the low in Low Franconian, Low German, etc., is in reference, not to these languages stature or prestige, but to their situation in the Low Countries (Netherlands, Niederland) as opposed to the highlands: cf. Upper and Lower Lusatia, Lower Saxony, etc. Sometimes, instead of flat plains (or steppes) and high mountains, it's just a reference to north and south.

Ceci n'est pas un seing.