The story
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: A wheel for a motor vehicle, made from an alloy of magnesium, typically lighter and offering better heat conduction than steel wheels; often styled in a five-point star pattern; (sometimes also) a wheel made to look like such wheels but not truly of magnesium. Full definition →
Etymology from Wiktionary, CC BY-SA 4.0.