Rimwards is a direction popularized by Terry Pratchett’s Discworld series.
The main idea is that if you are standing on a disc, and face the rim or edge of the disc, then you are oriented rimwards. The opposite orientation is hubwards.
Up and down are inappropriate terms. As are north and south, since neither exist.
East and west do not exist either on a disc, due to it’s nature, and hemispheres cannot be identified. So, in their place we get turnwise, and widdershins.