I'm not a native speaker of English.
The word "star", as a celestial object, is usually (or nearly always) defined as, well, e.g. the Sun, Sirius etc in dictionaries.
However, it seems unnatural to me, being "too technical" despite of the very elementary nature of the word "star". In fact, it originally meant, and remains to mean today, any bright dot in the night sky. (cf. shooting star, morning star... See also the first definition of Wiktionary)
What does the word "star" exactly mean for ordinary people? For example, suppose an adult friend of yours says "Look at that star!", and you reply "No, it's a planet," can it sound like you're looking down at them? If it is a child who says so, isn't such reply too difficult? Or even most 6-year old kids ditinguish the notion of star from that of planet? (Anyway visual distinction is a different matter.)
EDIT: Maybe my question can be summarized as: "Is it wrong/strange to count planets, commets and perhaps meteors that you see as stars?"
BTW in Japanese, the word 「星」 means "any" stars, while the word 「恒星」 is for nuclear fusion stars. The letter 「恒」 means "constant", so the literal meaning of 「恒星」 is close to the word "fixed star". (I guess 恒星 was coined as a translation of "fixed star".)