1. originating, existing, or occurring outside Earth or its atmosphere

1. a hypothetical or fictional being from outer space

Examples

• Scientists search for extraterrestrial life in distant galaxies.
• The movie featured friendly extraterrestrial visitors from Mars.
• Extraterrestrial rocks sometimes fall to Earth as meteorites.
• The radio telescope detected what might be an extraterrestrial signal.
• Many people claim to have seen extraterrestrials, but there’s no proof.
• The spacecraft was designed to study extraterrestrial environments.
• The novel described an extraterrestrial civilization on a distant planet.