The symbol on a map that shows directions is called a compass rose.
There are many varieties of compass rose. The simple most 4 points
compass rose simply shows the basic four cardinal directions, i.e
North/South/East/West. The slightly more complex one is 8 points compass
rose and that uses the principal wind to show 4 cardinal directions
(N/S/E/W) as well as four ordinal directions (NE, SE, SW, NW). The more
complex ones are 16 points as well as 32 points compass rose. These are
made by further bisecting the angles of 8 points or 16 points
respectively and could show a direction difference of quarter-winds at
22 1⁄2° (for 16 points) or 11 1⁄4° (for 32 points). There are also many
variants of compass rose available, such as Classical compass rose,
Sidereal compass rose, Mariner's compass rose etc.
