The shape is a five pointed star.
The initial usage of the star was for the eco mode on my primary tester's dishwasher. She equated the star with the EPA's energy star symbol. The usage expanded to represent a smart mode and an automatic mode. A star student is a smart student so that makes sense. Automatic mode implies there is some additional logic to an operation so an automatic mode may be smart too. Since then I have used a leaf shape for eco mode because sometimes eco mode doesn't necessarily mean smarter, it just means frugal, less wasteful. Thinking beyond appliance controls I do believe eco mode is smart but in practical application I'm pretty sure the auto mode on my dishwasher is not eco-friendly.
As with other shapes that have points, the star points are rounded. Also I tried to minimize the inner cut depth.