"Friesic" is a word in ENGLISH

Of or pertaining to Friesland, a province in the northern
part of the Netherlands.

The language of the Frisians, a Teutonic people formerly
occupying a large part of the coast of Holland and Northwestern
Germany. The modern dialects of Friesic are spoken chiefly in the
province of Friesland, and on some of the islands near the coast of
Germany and Denmark.