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adjective ter·res·tri·al \tə-ˈres-t(r)ē-əl; -ˈres-chəl, -ˈresh-\

Simple Definition of terrestrial

  • : relating to or occurring on the earth

  • : living or growing on land instead of in water or air

  • : sending a broadcast signal from the Earth

Source: Merriam-Webster's Learner's Dictionary

Full Definition of terrestrial

  1. 1a :  of or relating to the earth or its inhabitants <terrestrial magnetism>b :  mundane in scope or character :  prosaic

  2. 2a :  of or relating to land as distinct from air or water <terrestrial transportation>b (1) :  living on or in or growing from land <terrestrial plants> <terrestrial birds> (2) :  of or relating to terrestrial organisms <terrestrial habits>

  3. 3 :  belonging to the class of planets that are like the earth (as in density and silicate composition) <the terrestrial planets Mercury, Venus, and Mars>

terrestrial noun
terrestrially adverb

Examples of terrestrial in a sentence

  1. The toad has terrestrial habits, spending most of its time on shore.

  2. <scientists haven't even found all the terrestrial life on our planet>

Did You Know?

Terrestrial might be a pretty down-to-earth word, but some of its relatives are out of this world. "Terrestrial" first appeared in English in the 15th century and derives from the Latin root terra, which means "earth." In the mid-1800s "extra-" was added to "terrestrial," giving us "extraterrestrial," an adjective that can be used to describe things (including science fiction creatures) that come from space. "Terrestrial" shares the "-al" suffix with "celestial," which was first used in the 14th century. Not surprisingly, "celestial" ("of or relating to the sky or visible heavens") traces back to the Latin for sky, "caelum."

Origin of terrestrial

Middle English, from Latin terrestris, from terra earth — more at terrace

First Known Use: 15th century

TERRESTRIAL Defined for Kids


adjective ter·res·tri·al \tə-ˈre-strē-əl\

Definition of terrestrial for Students

  1. 1 :  relating to the earth or its people <Does anything like terrestrial life exist on other planets?>

  2. 2 :  living or growing on land <terrestrial birds>

Word Root of terrestrial

The Latin word terra, meaning “earth,” “land,” or “ground,” gives us the root terr. Words from the Latin terra have something to do with the earth or land. A territory is an area of land ruled by a particular government. A terrace is a piece of land with a flat top. Anything terrestrial lives on land and not in water.

Seen and Heard

What made you want to look up terrestrial? Please tell us where you read or heard it (including the quote, if possible).


to expose to danger or risk

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