This refers to a star that appears in the sky. During the Jaahiliyyah, people thought that the stars influenced events on earth, so they would attribute events to the stars. This corrupt belief has come down to people in our own time, and they say things like this, but many people do not know what this means. It is Haraam to use the phrases “because of a lucky star” and “because of an unlucky star,” because this is attributing what happens in the universe, good or bad, to the stars, when in reality the stars have no impact at all and they are not a cause of good luck or bad luck. Allah says: Unquestionably, His is the creation and the command; blessed is Allah, Lord of the worlds. [7:54].