extraterrestrial

1 of 2

adjective

ex·​tra·​ter·​res·​tri·​al ˌek-strə-tə-ˈre-strē-əl 

-ˈres-chəl, 

-ˈresh-chəl

: originating, existing, or occurring outside the earth or its atmosphere

extraterrestrial life

extraterrestrial

2 of 2

noun

: a being from another world : an extraterrestrial being

Examples of extraterrestrial in a Sentence

Recent Examples on the Web

Adjective

An extraterrestrial settlement in an environment like Mars — with its lack of magnetic field and thin, toxic atmosphere — would likely necessitate the invention of numerous new technologies. — Jackie Wattles, CNN Money, 24 June 2026

Ultimately, these technological improvements will inform the design of next-generation rovers capable of exploring previously inaccessible, rough extraterrestrial landscapes. — Mrigakshi Dixit, Interesting Engineering, 19 June 2026

Noun

These days, those same thinkers describe their object of study as Unidentified Aerial Phenomena—and universities, governmental agencies, and independent groups are devoting serious resources to finally getting to the bottom of whether extraterrestrials really are out there. — Erin Vanderhoof, Vanity Fair, 19 June 2026

The extraterrestrials wiped Daniel and Margaret’s memories of that night, knowing that when the aliens someday returned, the pair would be able to relay their otherworldly messages to the citizens of Earth. — Patrick Ryan, USA Today, 13 June 2026

Word History

First Known Use

Adjective

1848, in the meaning defined above

Noun

1950, in the meaning defined above

Rhymes for extraterrestrial

• estriol
• terrestrial

Kids Definition

extraterrestrial

adjective

ex·​tra·​ter·​res·​tri·​al

ˌek-strə-tə-ˈres-trē-əl

: coming from or existing outside the earth or its atmosphere

extraterrestrial life

extraterrestrial noun