Literally, it means to take a course opposite the apparent motion of the sun viewed from the Northern Hemisphere. Widdershins is cognate with the German widersinnig, i.e., “against” + “sense”. The opposite of widdershins is deosil, or sunwise, meaning “clockwise”.
Not only that but most of them are played down not up when compared to real life. The discworld is a lot less weird than real life.