planet
/'plænit/
Học thuậtThân thiện
Definition
- Noun:
- A celestial body in orbit around a star: A "planet" is a large, round object in space that moves in a regular, curved path (an orbit) around a star, such as the Sun. It does not produce its own light but shines by reflecting the light of its star.
- A major body in a solar system: Specifically, in our solar system, a "planet" is one of the eight large celestial bodies (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune) that orbit the Sun. This definition excludes comets, asteroids, and moons.
- (Archaic/Figurative) A person of great influence: In older or figurative use, a "planet" can refer to a person who is a dominant influence or who is seen as revolving around another, more important figure.
Examples of Usage
- Noun:
- Earth is the third planet from the Sun.
- Scientists are searching for planets in other solar systems that might support life.
- In the old astrology, the prince was considered a planet around which the court revolved.
Advanced Usage
- "Dwarf planet": A celestial body that orbits the Sun and is round due to its own gravity but has not cleared its orbital path of other debris (e.g., Pluto, Ceres).
- Pluto was reclassified as a dwarf planet in 2006.
- "Exoplanet" or "extrasolar planet": A planet that orbits a star outside our solar system.
- The discovery of a new exoplanet in the habitable zone excited astronomers.
Variants and Related Words
- Planetary (adj): Relating to a planet or planets.
- The planetary alignment was visible last night.
- Interplanetary (adj): Existing or occurring between planets.
- Interplanetary travel is a goal for future space exploration.
Synonyms
- Orb: (Poetic/Archaic) A celestial body, especially a planet or star.
- World: Often used to refer to a planet, especially when considering it as a place where life could exist (e.g., "alien worlds").
Related Phrases
- Planet Earth: A specific reference to our own planet.
- We must take care of Planet Earth.
- Inner/Outer planet: A classification based on position relative to the asteroid belt. Inner planets (Mercury, Venus, Earth, Mars) are rocky; outer planets (Jupiter, Saturn, Uranus, Neptune) are gas giants.
- Jupiter is the largest of the outer planets.
Related Idioms
- What planet is someone on?: A rhetorical question implying that someone's ideas or behavior are very strange, out of touch, or illogical.
- He thinks we can finish this in an hour. What planet is he on?
- To be on another planet: To be daydreaming, not paying attention, or completely mistaken about a situation.
- Sorry, I didn't hear you; I was on another planet for a moment.
Noun
- any celestial body (other than comets or satellites) that revolves around a star
- a person who follows or serves another
- (astronomy) any of the nine large celestial bodies in the solar system that revolve around the sun and shine by reflected light; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto in order of their proximity to the sun; viewed from the constellation Hercules, all the planets rotate around the sun in a counterclockwise direction